Find the equation of the tangent line to the graph of f(x)=−2xln(x+7) at x=−3.

The equation of the tangent line is y = -14.5x - 39.

f(-3) = 6ln4
f'(x) = -2x/(x+7) - 2ln(x+7)
f'(-3) = 3/2 - 2ln4
so the line is
y-6ln4 = (3/2 - 2ln4)(x+3)
or
y = -1.27(x+3) + 8.32 = -1.27x + 4.51