I'll do a different problem that's worked exactly the same way, so
you won't be getting credit for what somebody else did. I'll do this
one instead:
Find an equation of the line with the given slope and containing the given
point. Write the equation using function notation.
Slope -3 (5,9)y - y1 = m(x - x1)
y - 9 = -3(x - 5)
y - 9 = -3x + 15
y = -3x + 24
To use function notation, substitute f(x) for y
f(x) = -3x + 24
Now do yours the exact same way.
Edwin