# How do you write the equation in slope intercept form given (1, -5) and (-3, 7)?

##### 1 Answer

Mar 8, 2016

y = -3x -2

#### Explanation:

The equation in slope-intercept form is y = mx + c , where m represents gradient (slope) and c , the y-intercept.

Require to find m and c. m can be found using the

#color(blue)" gradient formula "#

# m = (y_2 - y_1)/(x_2 - x_1 ) # where

#(x_1,y_1) " and " (x_2,y_2)" are coords of 2 points "# let

#(x_1,y_1)=(1,-5)" and " (x_2,y_2)=(-3,7) # hence:

#m = (7-(-5))/(-3-1) = 12/(-4) = -3 # partial equation is : y = -3x + c

To find c , use either of the 2 given points.

using (1,-5) : -3(1) + c = -5 → c = - 2

#rArr y = - 3x -2 " is the equation " #