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Example Questions
Example Question #41 : Evaluating And Simplifying Expressions
Which of the following operations could represent the expression ?
2 times 7 less than the square of x
7 less than the square of 2x
7 more than 2 times the square of x
7 more than the square of 2x
2 times 7 more than the square of x
7 more than 2 times the square of x
Begin by putting the equation given into your own words. It might sound something similar to:
2 times x squared plus 7
Now, go through each answer choice and see if any of them are similar to this. We immediately see that the answer "7 more than 2 times the square of x" is similar to what we came up with. Let's do a quick run through of the other choices to be sure of our choice:
"2 times 7 more than the square of x" is equal to , which is equivalent to
.
"2 times 7 less than the square of x" is equal to , which is equivalent to
.
"7 more than the square of 2x" is equal to , which is equivalent to
.
"7 less than the square of 2x" is equal to , which is equivalent to
.
The only answer that works is "7 more than 2 times the square of x". This is the correct answer.
Example Question #3 : How To Simplify An Expression
What does equal?
When solving a complex expression, remember the acronym PEMDAS (Parentheses, Exponents, Multiplication, Division, Addition, Subtraction). Reading left to right, begin by doing all operations within the innermost Parentheses first:
Continue simplifying using the acronym PEMDAS:
The expression is equal to -63.
Example Question #1 : Rational Expressions
Simplify.
Same denominator means you add straight across the numerators, keeping the denominator the same.
Add like terms.
Final Answer.
Example Question #2 : Rational Expressions
Simplify.
Check for same Denominator
Add like terms
Check for GCF or if the expression can be factored
After factoring, divide out like terms.
Final Answer
Example Question #11 : Rational Expressions
Simplify the following rational expression: (9x - 2)/(x2) MINUS (6x - 8)/(x2)
Since both expressions have a common denominator, x2, we can just recopy the denominator and focus on the numerators. We get (9x - 2) - (6x - 8). We must distribute the negative sign over the 6x - 8 expression which gives us 9x - 2 - 6x + 8 ( -2 minus a -8 gives a +6 since a negative and negative make a positive). The numerator is therefore 3x + 6.
Example Question #311 : Algebra
Simplify the expression.
To add rational expressions, first find the least common denominator. Because the denominator of the first fraction factors to 2(x+2), it is clear that this is the common denominator. Therefore, multiply the numerator and denominator of the second fraction by 2.
This is the most simplified version of the rational expression.
Example Question #1 : Expressions
If √(ab) = 8, and a2 = b, what is a?
10
4
16
2
64
4
If we plug in a2 for b in the radical expression, we get √(a3) = 8. This can be rewritten as a3/2 = 8. Thus, loga 8 = 3/2. Plugging in the answer choices gives 4 as the correct answer.
Example Question #2 : Expressions
37/15
9/5
–11/5
–37/15
–9/5
–11/5
Example Question #3 : Rational Expressions
Simplify.
Determine an LCD (Least Common Denominator) between and
.
LCD =
Multiply the top and bottom of the first rational expression by , so that the denominator will be
.
Distribute the to
.
Now you can subtract because both rational expressions have the same denominators.
Final Answer.
Example Question #1 : Rational Expressions
Which of the following is equivalent to ? Assume that denominators are always nonzero.
We will need to simplify the expression . We can think of this as a large fraction with a numerator of
and a denominator of
.
In order to simplify the numerator, we will need to combine the two fractions. When adding or subtracting fractions, we must have a common denominator. has a denominator of
, and
has a denominator of
. The least common denominator that these two fractions have in common is
. Thus, we are going to write equivalent fractions with denominators of
.
In order to convert the fraction to a denominator with
, we will need to multiply the top and bottom by
.
Similarly, we will multiply the top and bottom of by
.
We can now rewrite as follows:
=
Let's go back to the original fraction . We will now rewrite the numerator:
=
To simplify this further, we can think of as the same as
. When we divide a fraction by another quantity, this is the same as multiplying the fraction by the reciprocal of that quantity. In other words,
.
=
Lastly, we will use the property of exponents which states that, in general, .
The answer is .
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