Answer:
y = -6x -9
Step-by-step explanation:
The derivative is ...
f'(x) = 2x
so the slope at x=-3 is ...
f'(-3) = 2(-3) = -6
Then the point-slope form of the tangent line can be written ...
y = m(x -h) +k . . . . . . for line with slope m through point (h, k)
y = -6(x -(-3))+9 = -6x -18 +9 . . . . . filling in your values, eliminating parens
So, the slope-intercept equation of the tangent line is ...
y = -6x -9
