SATMathematics Practice Test 1

To solve for t, factor the left side of ${\mathit{t}}^2-4=0$, giving $\left(\mathit{t}-2\right)\left(\mathit{t}+2\right)=0$.
Therefore, either $\mathit{t}-2=0$ or $\mathit{t}+2=0$.
If $\mathit{t}-2=0$, then $\mathit{t}=2$, and if $\mathit{t}+2=0$, then $\mathit{t}=-2$.
Since it is given that $\mathit{t}>0$, the value of t must be 2.
Another way to solve for t is to add 4 to both sides of ${\mathit{t}}^2-4=0$, giving ${\mathit{t}}^2=4$ .
Then, taking the square root of the left and the right side of the equation gives $\mathit{t}=\pm \sqrt{4}=\pm 2$.
Since it is given that $\mathit{t}>0$, the value of t must be 2.