Need help on the last problem please

Step-by-step explanation:

Derivative is the slope of the tangent line at any point.

That slope is positive for x < -5 and x > 0

That slope is negative for -5 < x < 0

answer: the angel abc is 30°,and the abc is a triangle where the angel bac is 90°

so ac is the half of 24=12ft,and from the pythagorean theorem we find ba

ba=√bc^2-ac^2=√576-144=√432=12√3ft

so bac is 12+12√3=12(1+√3)ft