Andrew can reach a maximum of [tex]24.6ft[/tex] high up the wall.
The right-angled triangle formed can be solved using the [tex]sine[/tex] ratio. that is
[tex]sin(72^\circ})=\dfrac{h}{20}[/tex]
where [tex]h[/tex] is the distance from the foot of the wall to the tip of the ladder where it rests on the wall. Substituting, and solving for [tex]h[/tex], we get
[tex]0.9816=\dfrac{h}{20}\\\\h=20\times0.9816\\\\h=19.632ft[/tex]
Since Andrew can reach an extra [tex]5ft[/tex] above the point where the ladder rests against the wall, the maximum height Andrew can paint is
[tex](19.632+5)ft=24.632ft\\\\\approx24.6ft[/tex]
Another solved word problem on trigonometry can be found here: https://brainly.com/question/12146092
