Simple....
assuming you have studied Pythagorean Theorem...
[tex]a^{2} + b^{2} = c^{2} [/tex]
If it leans 12 ft...then c=12
the base is at 3 ft or b=3
You need to find a....
[tex] a^{2}+ 3^{2} = 12^{2} [/tex]
[tex] a^{2} +9=144
[/tex]
-9 -9
[tex] a^{2} =135[/tex]
Square root.....
[tex] \sqrt{135} =11.6[/tex]
You are measuring to the nearest tenth.
Thus, your answer....11.6 ft.
