Question

Using the point-slope equation, find the equation containing (-5, -8) and slope m = -3

Answer 1

Point slope form is y=y1+m(x-x1) where (x1,y1) is a point and m is your slope..
Plugging the values in:
y=-8 -3(x+5)

Answer 2

y+8=-3(x+5) {using formula y-y1=m(x-x1)}
3x+y +23=0

Answer 3

You can further simplify by distributing the -3 through, and adding like terms.
y=-8-3x-15
Add -8 and -15 together, -23
so y=-3x -23