Answer:
8 ft
Step-by-step explanation:
the ladder will make a right angle triangle with the house. The hypotenuse of the triangle is the ladder, 20 ft, and the height of the triagnle is 18 ft.
Solve for the base of the right angle triangle using pythagorean's theorem:
c=20, a=18, b=?
[tex]b^{2}=c^{2} - a^{2}\\b^{2}=20^{2} - 18^{2}[/tex]
[tex]b=\sqrt{72}[/tex]
[tex]b= 8.49 ft[/tex]
round to the nearest foot,
b = 8 ft
