Study Radicals And Absolute Values in SAT Math with focused flashcards that help you recognize the idea, recall the key rule, and apply it in practice-style prompts.
All flashcards Flashcard 1: Simplify √ 18 √ 2 \frac{\text{√}18}{\text{√}2} √ 2 √ 18 . Answer: √ 9 = 3 \text{√}9 = 3 √ 9 = 3 . Simplify by dividing: 18 2 = 18 2 = 9 \frac{\sqrt{18}}{\sqrt{2}} = \sqrt{\frac{18}{2}} = \sqrt{9} 2 18 = 2 18 = 9 .
Flashcard 2: State the property: ∣ a ∣ + ∣ b ∣ ≠ ? |\text{a}| + |\text{b}| \neq ? ∣ a ∣ + ∣ b ∣ = ? Answer: ∣ a + b ∣ |\text{a} + \text{b}| ∣ a + b ∣ . Triangle inequality shows they're not always equal.
Flashcard 3: Simplify √ 12 − √ 3 \text{√}12 - \text{√}3 √ 12 − √ 3 . Answer: 3 √ 3 − √ 3 = 2 √ 3 3\text{√}3 - \text{√}3 = 2\text{√}3 3 √ 3 − √ 3 = 2 √ 3 . Simplify radicals first: 12 = 2 3 \sqrt{12} = 2\sqrt{3} 12 = 2 3 .
Flashcard 4: Simplify √ 72 \text{√}72 √ 72 . Answer: 6 √ 2 6\text{√}2 6 √ 2 . Factor out perfect squares: 72 = 36 × 2 \sqrt{72} = \sqrt{36 \times 2} 72 = 36 × 2 .
Flashcard 5: What is the principal square root of 81? Answer:
Since 9 × 9 = 81 9 \times 9 = 81 9 × 9 = 81 .
Flashcard 6: What is the absolute value of 0? Answer:
Zero has no distance from itself.
Flashcard 7: Simplify √ 50 \text{√}50 √ 50 . Answer: 5 √ 2 5\text{√}2 5 √ 2 . Factor out perfect squares: 50 = 25 × 2 \sqrt{50} = \sqrt{25 \times 2} 50 = 25 × 2 .
Flashcard 8: What is the absolute value of -15? Answer:
Absolute value makes any number non-negative.
Flashcard 9: What is the square root of 49? Answer:
Since 7 × 7 = 49 7 \times 7 = 49 7 × 7 = 49 .
Flashcard 10: Solve for x x x : ∣ x + 5 ∣ = 8 |\text{x} + 5| = 8 ∣ x + 5∣ = 8 . Answer: x = 3 x = 3 x = 3 or x = − 13 x = -13 x = − 13 . Distance from -5 equals 8, so x + 5 = ± 8 x + 5 = \pm 8 x + 5 = ± 8 .
Flashcard 11: Simplify: sqrt ( 72 ) \text{sqrt}(72) sqrt ( 72 ) . Answer: 6 sqrt ( 2 ) 6\text{sqrt}(2) 6 sqrt ( 2 ) . Factor out perfect squares: 36 × 2 = 6 2 \sqrt{36 \times 2} = 6\sqrt{2} 36 × 2 = 6 2 .
Flashcard 12: State the property: ∣ a ∣ × ∣ b ∣ = ? |\text{a}| \times |\text{b}| = ? ∣ a ∣ × ∣ b ∣ = ? Answer: ∣ a × b ∣ |\text{a} \times \text{b}| ∣ a × b ∣ . Absolute values multiply to give the absolute value of the product.
Flashcard 13: Simplify √ 45 √ 5 \frac{\text{√}45}{\text{√}5} √ 5 √ 45 . Answer: √ 9 = 3 \text{√}9 = 3 √ 9 = 3 . Divide radicals: 45 5 = 45 5 = 9 \frac{\sqrt{45}}{\sqrt{5}} = \sqrt{\frac{45}{5}} = \sqrt{9} 5 45 = 5 45 = 9 .
Flashcard 14: What is the square root of 49? Answer:
Since 7 × 7 = 49 7 \times 7 = 49 7 × 7 = 49 .
Flashcard 15: Solve for x x x : ∣ 3x + 2 ∣ = 11 |\text{3x} + 2| = 11 ∣ 3x + 2∣ = 11 . Answer: x = 3 x = 3 x = 3 or x = − 13 3 x = -\frac{13}{3} x = − 3 13 . Distance equals 11, so 3 x + 2 = ± 11 3x + 2 = \pm 11 3 x + 2 = ± 11 .
Flashcard 16: Solve for x x x : ∣ 3x + 2 ∣ = 11 |\text{3x} + 2| = 11 ∣ 3x + 2∣ = 11 . Answer: x = 3 x = 3 x = 3 or x = − 13 3 x = -\frac{13}{3} x = − 3 13 . Distance equals 11, so 3 x + 2 = ± 11 3x + 2 = \pm 11 3 x + 2 = ± 11 .
Flashcard 17: Simplify √ 8 + √ 18 \text{√}8 + \text{√}18 √ 8 + √ 18 . Answer: 2 √ 2 + 3 √ 2 = 5 √ 2 2\text{√}2 + 3\text{√}2 = 5\text{√}2 2 √ 2 + 3 √ 2 = 5 √ 2 . Simplify each radical first: 8 = 2 2 \sqrt{8} = 2\sqrt{2} 8 = 2 2 , 18 = 3 2 \sqrt{18} = 3\sqrt{2} 18 = 3 2 .
Flashcard 18: What is the absolute value of -15? Answer:
Absolute value makes any number non-negative.
Flashcard 19: What is the result of √ 1 \text{√}1 √ 1 ? Answer:
Since 1 × 1 = 1 1 \times 1 = 1 1 × 1 = 1 .
Flashcard 20: Simplify √ 50 \text{√}50 √ 50 . Answer: 5 √ 2 5\text{√}2 5 √ 2 . Factor out perfect squares: 50 = 25 × 2 \sqrt{50} = \sqrt{25 \times 2} 50 = 25 × 2 .
Flashcard 21: Solve for x x x : √ x = 5 \text{√}x = 5 √ x = 5 . Answer: x = 25 x = 25 x = 25 . Square both sides to eliminate the radical.
Flashcard 22: State the property: ∣ a × b ∣ |\text{a} \times \text{b}| ∣ a × b ∣ . Answer: ∣ a × b ∣ = ∣ a ∣ × ∣ b ∣ |\text{a} \times \text{b}| = |\text{a}| \times |\text{b}| ∣ a × b ∣ = ∣ a ∣ × ∣ b ∣ . The absolute value of a product equals the product of absolute values.
Flashcard 23: Simplify √ 20 \text{√}20 √ 20 . Answer: 2 √ 5 2\text{√}5 2 √ 5 . Factor out perfect squares: 20 = 4 × 5 \sqrt{20} = \sqrt{4 \times 5} 20 = 4 × 5 .
Flashcard 24: What is the absolute value of ∣ 3 − 7 ∣ |\text{3} - 7| ∣ 3 − 7∣ ? Answer:
Calculate 3 − 7 = − 4 3 - 7 = -4 3 − 7 = − 4 , then take absolute value.
Flashcard 25: Express √ 32 \text{√}32 √ 32 in simplest radical form. Answer: 4 √ 2 4\text{√}2 4 √ 2 . Factor out perfect squares: 32 = 16 × 2 \sqrt{32} = \sqrt{16 \times 2} 32 = 16 × 2 .
Flashcard 26: What is √ 64 \text{√}64 √ 64 ? Answer:
Since 8 × 8 = 64 8 \times 8 = 64 8 × 8 = 64 .
Flashcard 27: What is the result of ∣ -25 ∣ |\text{-25}| ∣ -25 ∣ ? Answer:
Absolute value removes the negative sign.
Flashcard 28: Solve for x x x : √ x = 5 \text{√}x = 5 √ x = 5 . Answer: x = 25 x = 25 x = 25 . Square both sides to eliminate the radical.
Flashcard 29: What is √ 64 \text{√}64 √ 64 ? Answer:
Since 8 × 8 = 64 8 \times 8 = 64 8 × 8 = 64 .
Flashcard 30: Simplify: 48 + 12 \sqrt{48} + \sqrt{12} 48 + 12 . Answer: 6 3 6\sqrt{3} 6 3 . Simplify to 4 3 + 2 3 = 6 3 4\sqrt{3} + 2\sqrt{3} = 6\sqrt{3} 4 3 + 2 3 = 6 3 .
Flashcard 31: What is the absolute value of ∣ -7 ∣ |\text{-7}| ∣ -7 ∣ ? Answer:
Absolute value makes negative numbers positive.
Flashcard 32: Simplify 18 2 \frac{\sqrt{18}}{\sqrt{2}} 2 18 . Answer: 9 = 3 \sqrt{9} = 3 9 = 3 . Simplify by dividing: 18 2 = 18 2 = 9 \frac{\sqrt{18}}{\sqrt{2}} = \sqrt{\frac{18}{2}} = \sqrt{9} 2 18 = 2 18 = 9 .
Flashcard 33: Solve for x x x : ∣ x ∣ = 12 |\text{x}| = 12 ∣ x ∣ = 12 . Answer: x = 12 x = 12 x = 12 or x = − 12 x = -12 x = − 12 . Absolute value equation has two solutions: x = ± 12 x = \pm 12 x = ± 12 .
Flashcard 34: What is the square root of 64? Answer:
Since 8 2 = 64 8^2 = 64 8 2 = 64 , the principal square root is 8.
Flashcard 35: Solve for x x x : ∣ x ∣ = 12 |\text{x}| = 12 ∣ x ∣ = 12 . Answer: x = 12 x = 12 x = 12 or x = − 12 x = -12 x = − 12 . Absolute value equation has two solutions: x = ± 12 x = \pm 12 x = ± 12 .
Flashcard 36: Simplify √ 0.25 \text{√}0.25 √ 0.25 . Answer: 0.5. Since 0.5 × 0.5 = 0.25 0.5 \times 0.5 = 0.25 0.5 × 0.5 = 0.25 .
Flashcard 37: Simplify: 50 2 \frac{\sqrt{50}}{\sqrt{2}} 2 50 . Answer: 25 = 5 \sqrt{25} = 5 25 = 5 . This simplifies to 25 = 5 \sqrt{25} = 5 25 = 5 using the quotient property of radicals.
Flashcard 38: What is the value of ∣ -7 ∣ |\text{-7}| ∣ -7 ∣ ? Answer:
Absolute value gives the distance from zero, always positive.
Flashcard 39: Simplify √ 45 √ 5 \frac{\text{√}45}{\text{√}5} √ 5 √ 45 . Answer: √ 9 = 3 \text{√}9 = 3 √ 9 = 3 . Divide radicals: 45 5 = 45 5 = 9 \frac{\sqrt{45}}{\sqrt{5}} = \sqrt{\frac{45}{5}} = \sqrt{9} 5 45 = 5 45 = 9 .
Flashcard 40: Solve for x x x : ∣ x + 5 ∣ = 8 |\text{x} + 5| = 8 ∣ x + 5∣ = 8 . Answer: x = 3 x = 3 x = 3 or x = − 13 x = -13 x = − 13 . Distance from -5 equals 8, so x + 5 = ± 8 x + 5 = \pm 8 x + 5 = ± 8 .
Flashcard 41: What is the result of √ 1 \text{√}1 √ 1 ? Answer:
Since 1 × 1 = 1 1 \times 1 = 1 1 × 1 = 1 .
Flashcard 42: Simplify √ 72 \text{√}72 √ 72 . Answer: 6 √ 2 6\text{√}2 6 √ 2 . Factor out perfect squares: 72 = 36 × 2 \sqrt{72} = \sqrt{36 \times 2} 72 = 36 × 2 .
Flashcard 43: What is the value of ∣ − 7 ∣ |-7| ∣ − 7∣ ? Answer:
Absolute value gives the distance from zero, always positive.
Flashcard 44: State the property: ∣ a ∣ × ∣ b ∣ = ? |\text{a}| \times |\text{b}| = ? ∣ a ∣ × ∣ b ∣ = ? Answer: ∣ a × b ∣ |\text{a} \times \text{b}| ∣ a × b ∣ . Absolute values multiply to give the absolute value of the product.
Flashcard 45: What is the result of ∣ 5 − 9 ∣ |5 - 9| ∣5 − 9∣ ? Answer:
Calculate 5 − 9 = − 4 5 - 9 = -4 5 − 9 = − 4 , then take absolute value to get 4.
Flashcard 46: Simplify √ 12 − √ 3 \text{√}12 - \text{√}3 √ 12 − √ 3 . Answer: 3 √ 3 − √ 3 = 2 √ 3 3\text{√}3 - \text{√}3 = 2\text{√}3 3 √ 3 − √ 3 = 2 √ 3 . Simplify radicals first: 12 = 2 3 \sqrt{12} = 2\sqrt{3} 12 = 2 3 .
Flashcard 47: What is √ ( − 9 ) \text{√}(-9) √ ( − 9 ) ? Answer: Not a real number. Square roots of negative numbers aren't real.
Flashcard 48: What is the result of ∣ 5 − 9 ∣ |5 - 9| ∣5 − 9∣ ? Answer:
Calculate 5 − 9 = − 4 5 - 9 = -4 5 − 9 = − 4 , then take absolute value to get 4.
Flashcard 49: Solve for x x x : ∣ x − 3 ∣ = 5 |x - 3| = 5 ∣ x − 3∣ = 5 . Answer: x = 8 x = 8 x = 8 or x = − 2 x = -2 x = − 2 . Distance from 3 equals 5, so x − 3 = 5 x - 3 = 5 x − 3 = 5 or x − 3 = − 5 x - 3 = -5 x − 3 = − 5 .
Flashcard 50: What is the cube root of 27? Answer:
Since 3 3 = 27 3^3 = 27 3 3 = 27 , the cube root is 3.
Flashcard 51: What is the absolute value of ∣ 3 − 7 ∣ |\text{3} - 7| ∣ 3 − 7∣ ? Answer:
Calculate 3 − 7 = − 4 3 - 7 = -4 3 − 7 = − 4 , then take absolute value.
Flashcard 52: Simplify √ 200 \text{√}200 √ 200 . Answer: 10 √ 2 10\text{√}2 10 √ 2 . Factor out perfect squares: 200 = 100 × 2 \sqrt{200} = \sqrt{100 \times 2} 200 = 100 × 2 .
Flashcard 53: What is the principal square root of 81? Answer:
Since 9 × 9 = 81 9 \times 9 = 81 9 × 9 = 81 .
Flashcard 54: Express √ 32 \text{√}32 √ 32 in simplest radical form. Answer: 4 √ 2 4\text{√}2 4 √ 2 . Factor out perfect squares: 32 = 16 × 2 \sqrt{32} = \sqrt{16 \times 2} 32 = 16 × 2 .
Flashcard 55: Simplify √ 20 \text{√}20 √ 20 . Answer: 2 √ 5 2\text{√}5 2 √ 5 . Factor out perfect squares: 20 = 4 × 5 \sqrt{20} = \sqrt{4 \times 5} 20 = 4 × 5 .
Flashcard 56: Solve for x x x : ∣ x − 4 ∣ = 3 |\text{x} - 4| = 3 ∣ x − 4∣ = 3 . Answer: x = 7 x = 7 x = 7 or x = 1 x = 1 x = 1 . Distance from 4 equals 3, so x − 4 = ± 3 x - 4 = \pm 3 x − 4 = ± 3 .
Flashcard 57: Solve for x x x : ∣ x − 3 ∣ = 5 |x - 3| = 5 ∣ x − 3∣ = 5 . Answer: x = 8 x = 8 x = 8 or x = − 2 x = -2 x = − 2 . Distance from 3 equals 5, so x − 3 = 5 x - 3 = 5 x − 3 = 5 or x − 3 = − 5 x - 3 = -5 x − 3 = − 5 .
Flashcard 58: Solve for x x x : ∣ 2x − 3 ∣ = 5 |\text{2x} - 3| = 5 ∣ 2x − 3∣ = 5 . Answer: x = 4 x = 4 x = 4 or x = − 1 x = -1 x = − 1 . Distance equals 5, so 2 x − 3 = ± 5 2x - 3 = \pm 5 2 x − 3 = ± 5 .
Flashcard 59: Simplify √ 0.25 \text{√}0.25 √ 0.25 . Answer: 0.5. Since 0.5 × 0.5 = 0.25 0.5 \times 0.5 = 0.25 0.5 × 0.5 = 0.25 .
Flashcard 60: Solve for x x x : ∣ x − 4 ∣ = 3 |\text{x} - 4| = 3 ∣ x − 4∣ = 3 . Answer: x = 7 x = 7 x = 7 or x = 1 x = 1 x = 1 . Distance from 4 equals 3, so x − 4 = ± 3 x - 4 = \pm 3 x − 4 = ± 3 .
Flashcard 61: State the property: ∣ a ∣ + ∣ b ∣ ≠ ? |\text{a}| + |\text{b}| \neq ? ∣ a ∣ + ∣ b ∣ = ? Answer: ∣ a + b ∣ |\text{a} + \text{b}| ∣ a + b ∣ . Triangle inequality shows they're not always equal.
Flashcard 62: Simplify √ 8 + √ 18 \text{√}8 + \text{√}18 √ 8 + √ 18 . Answer: 2 √ 2 + 3 √ 2 = 5 √ 2 2\text{√}2 + 3\text{√}2 = 5\text{√}2 2 √ 2 + 3 √ 2 = 5 √ 2 . Simplify each radical first: 8 = 2 2 \sqrt{8} = 2\sqrt{2} 8 = 2 2 , 18 = 3 2 \sqrt{18} = 3\sqrt{2} 18 = 3 2 .
Flashcard 63: What is the absolute value of 0? Answer:
Zero has no distance from itself.
Flashcard 64: Simplify √ 27 \text{√}27 √ 27 . Answer: 3 √ 3 3\text{√}3 3 √ 3 . Factor out perfect squares: 27 = 9 × 3 \sqrt{27} = \sqrt{9 \times 3} 27 = 9 × 3 .
Flashcard 65: Solve for x x x : ∣ 2x − 3 ∣ = 5 |\text{2x} - 3| = 5 ∣ 2x − 3∣ = 5 . Answer: x = 4 x = 4 x = 4 or x = − 1 x = -1 x = − 1 . Distance equals 5, so 2 x − 3 = ± 5 2x - 3 = \pm 5 2 x − 3 = ± 5 .
Flashcard 66: What is the absolute value of ∣ -7 ∣ |\text{-7}| ∣ -7 ∣ ? Answer:
Absolute value makes negative numbers positive.
Flashcard 67: Simplify: 50 2 \frac{\sqrt{50}}{\sqrt{2}} 2 50 . Answer: 25 = 5 \sqrt{25} = 5 25 = 5 . This simplifies to 25 = 5 \sqrt{25} = 5 25 = 5 using the quotient property of radicals.
Flashcard 68: Simplify: 48 + 12 \sqrt{48} + \sqrt{12} 48 + 12 Answer: 6 3 6\sqrt{3} 6 3 . Simplify to 4 3 + 2 3 = 6 3 4\sqrt{3} + 2\sqrt{3} = 6\sqrt{3} 4 3 + 2 3 = 6 3
Flashcard 69: What is the result of ∣ -25 ∣ |\text{-25}| ∣ -25 ∣ ? Answer:
Absolute value removes the negative sign.
Flashcard 70: What is √ ( − 9 ) \text{√}(-9) √ ( − 9 ) ? Answer: Not a real number. Square roots of negative numbers aren't real.
Flashcard 71: What is the square of √ 3 \text{√}3 √ 3 ? Answer:
The square of a square root equals the radicand.
Flashcard 72: Simplify √ 200 \text{√}200 √ 200 . Answer: 10 √ 2 10\text{√}2 10 √ 2 . Factor out perfect squares: 200 = 100 × 2 \sqrt{200} = \sqrt{100 \times 2} 200 = 100 × 2 .