To solve for , first subtract \(\displaystyle 71\) from both sides of the equation:

\(\displaystyle \frac{x}{9}+71-71=89-71\)

\(\displaystyle \frac{x}{9}=18\)

Then multiply each side of the equation by \(\displaystyle 9\):

\(\displaystyle \frac{x}{9}\cdot 9=18\cdot 9\)

\(\displaystyle x=162\)

To solve for \(\displaystyle x\), first distribute the \(\displaystyle -3\) outside the parentheses to both values inside the parentheses:

\(\displaystyle -3x-48=12\)

Then add \(\displaystyle 48\) to both sides of the equation:

\(\displaystyle -3x-48+48=12+48\)

\(\displaystyle -3x=60\)

Then divide both sides of the equation by \(\displaystyle -3\):

\(\displaystyle \frac{-3x}{-3}=\frac{60}{-3}\)

\(\displaystyle x=-20\)

To solve for , first subtract \(\displaystyle 64\) from both sides of the equation:

\(\displaystyle 8x+64-64=128-64\)

\(\displaystyle 8x=64\)

Then divide both sides of the equation by \(\displaystyle 8\):

\(\displaystyle \frac{8x}{8}=\frac{64}{8}\)

\(\displaystyle x=8\)

To solve for , first add \(\displaystyle 8\) to both sides of the equation:

\(\displaystyle \frac{x}{13}-8+8=6+8\)

\(\displaystyle \frac{x}{13}=14\)

Then multiply both sides of the equation by \(\displaystyle 13\):

\(\displaystyle \frac{x}{13}\cdot 13=14\cdot 13\)

\(\displaystyle x=182\)

To solve for \(\displaystyle x\), first distribute the \(\displaystyle -6\) outside the parentheses to both values inside the parentheses:

\(\displaystyle -6x+18=30\)

Then subtract \(\displaystyle 18\) from both sides of the equation:

\(\displaystyle -6x+18-18=30-18\)

\(\displaystyle -6x=12\)

Then divide both sides by \(\displaystyle -6\):

\(\displaystyle \frac{-6x}{-6}=\frac{12}{-6}\)

\(\displaystyle x=-2\)

To solve for , first divide both sides of the equation by \(\displaystyle 7\):

\(\displaystyle \frac{7x^{2}}{7}=\frac{112}{7}\)

\(\displaystyle x^{2}=16\)

Then take the square root of both sides of the equation:

\(\displaystyle \sqrt{x^{2}}=\sqrt{16}\)

\(\displaystyle x=4\)

However, remember that \(\displaystyle (-4)^{2}\) is also equal to \(\displaystyle 16\), so the answer is both positive and negative \(\displaystyle 4\).

\(\displaystyle x=\pm4\)

To solve for , first divide both sides of the equation by \(\displaystyle 4\):

\(\displaystyle \frac{4x^{2}}{4}=\frac{144}{4}\)

\(\displaystyle x^{2}=36\)

Take the square root of both sides of the equation:

\(\displaystyle \sqrt{x^{2}}=\sqrt{36}\)

\(\displaystyle x=6\)

However, remember that \(\displaystyle (-6)^{2}\) is also equal to \(\displaystyle 36\), so the answer is both positive and negative \(\displaystyle 6\).

\(\displaystyle x=\pm6\)

Plugging in \(\displaystyle 5\) for \(\displaystyle x\) gives \(\displaystyle 5 + 2(5)-3(5) +10\).

= \(\displaystyle 5+10-15+10\)

= \(\displaystyle 10\). 

This equation can be solved in three steps.

First, subtract \(\displaystyle 9\) from both sides of the equation to isolate the variable and its coefficient on the left side of the equation.

\(\displaystyle \frac{12}{x} + 9 = 13\)

\(\displaystyle \rightarrow (\frac{12}{x} + 9) - 9 = (13) - 9\)

\(\displaystyle \rightarrow \frac{12}{x} = 4\)

Now multiply both sides by \(\displaystyle x\) since \(\displaystyle x\) cannot be solved for while it is in the denominator.

\(\displaystyle (\frac{12}{x}) \times x = (4) \times x\)

\(\displaystyle \rightarrow 12 = 4x\)

Finally, divide both sides by \(\displaystyle 4\) to isolate \(\displaystyle x\) and find the solution.

\(\displaystyle \frac{(12)}{4} = \frac{(4x)}{4}\)

\(\displaystyle \rightarrow 3 = x\)

\(\displaystyle \frac{12}{a}-7=-1\)

Add 7 to both sides.

\(\displaystyle \frac{12}{a}-7+7=-1+7\)

\(\displaystyle \frac{12}{a}=6\)

Multiply both sides by \(\displaystyle \small a\).

\(\displaystyle \frac{12}{a}(a)=6a\)

\(\displaystyle 12=6a\)

Divide both sides by 6.

\(\displaystyle \frac{12}{6}=\frac{6a}{6}\)

\(\displaystyle 2=a\)