Chapter 2 Linear Equations and Functions - 2.4 Write Equations of Lines - Problem Solving Workshop - Practice - Page 105: 1

$y=4x+7$

We know that by the Slope Formula: if $P_1(x_1,y_1)$ and $P_2(x_2,y_2)$ are on a line, then the slope is: $m=\frac{y_2-y_1}{x_2-x_1}$. Hence here: $m=\frac{35-15}{7-2}=\frac{20}{5}=4.$ We know that if the slope of a line is $m$ and it contains $P_1(x_1,y_1)$, then its equation is: $y-y_1=m(x-x_1).$ Hence here: $y-15=4(x-2)\\y-15=4x-8\\y=4x+7$