Write an equation in point-slope form of the line through point j(–10, –9) with slope 3.

Use point-slope formula---> y-y1=m(x-x1)
Let y1 equal -9, let x1 equal -10, and let m equal 3 
Plug in and solve
y-(-9)=3(x-(-10)
y+9=3(x+10)
y+9=3x+30
Subtract nine from both sides 
y=3x+21(This is slope form, i might have gone too far)

A. -10 is the value of x