Solve the Problem $y = a x + b$ That Passes Through the Points

Multiple Choice

Solve the problem.
-Find the equation of the line $y = a x + b$ that passes through the points $( - 5,5 )$ and $( 3 , - 9 )$ .

A) $y = - \frac { 7 } { 4 } x - \frac { 15 } { 4 }$

B) $y = - \frac { 15 } { 4 } x - \frac { 7 } { 4 }$

C) $y = - \frac { 1 } { 2 } x + 1$

D) $y = - \frac { 7 } { 4 } x + \frac { 15 } { 2 }$