How do you factor and solve this equation?

y^2-2y-8=7

Ok so set one side equal to zero by subtractin g7

now we have

y^2-2y-15=0

if we factor then set each factor to zero we can solve becasue if we have

xy=0 then assume x and y=0 so

y^2-2y-15

find what 2 factors of - 15 add to - 2

-5 and 3

(x-5) (x+3)

tada

(x-5) (x+3) = 0

x-5=0

add 5

x=5

x+3=0

subtract 3

x=-3

x=5 or - 3