Question

What is the slope of the line that runs through points (-1,-7) and (2,5)?  Write the equation of that line.

Answer 1

Write slope intercept form general for the equation

y = mx + b

in this equation m = Y/X.

Y = y - y'

X = x - x'

then find m

m= (-7 -5)/ (-1 -2) = -12/-3 = 4

then equation becomes

y = 4x + b

b = y - 4x . Replace (x,y) = ( -1,-7)

b= -7 -4•(-1) = -3

Then finally eqaution of that line is

y = 4x -3