Which equation represents the line that passes through the points (–4, 3) and (2, –12)?

1 Answer
Jun 26, 2017

Equation y = -5/2 x -7 y=52x7

Explanation:

The slope m = (y_1 - y_2)/(x_1 - x_2) y1y2x1x2 Putting in the points gives

m = ( -12 - 3)/(2-( - 4)) 1232(4) This gives m = -15/6156
Dividing out common factors (\div 3)(÷3) gives m = -5/252

Putting this value in for m in the y = mx + b gives \color(blue)(y) = -5/2\color(red)(x) + by=52x+b
Now substitute one set of point values
\color(blue)(3)= -5/2(\color(red)(-4)) + b3=52(4)+b
solving for b gives 3 = 10 + b 3=10+b
subtract 10 from both sides 3- 10 = 10-10 + b 310=1010+b
-7 = b 7=b

\therefore y = -5/2 x -7