find an equation of the lin having the given slope and containing the given point.

M=-2 (5,9)

I got y=-2x - 19 for the answear

y = -2 x + b

9 = -2(5) + b
19 = b
so
y = -2 x + 19

check
9 = -2 (5) + 19 ?
9 = -10 + 19 ?
9 = 9 yes, check