you need to plug the numbers into point slope form
*y-y1=m(x-x1)
y and x standing for the coordinates (-3,0) so the equation would be if you plug the numbers in
y-0=3/2(x+3) *if its a negative make it positive if its a positive make it negative cause if you have lets say +-3 then it would just be -3
then from there just solve for y
btw the answer you have is wrong
