Question 858462
Because the wall and the ground are at a 90° angle to each other, those two are the legs, and the latter is the hypotenuse. To find the ground, first, we must use the pythagorean theorem:
{{{a^2+b^2=c^2}}}
Next, plug in known values:
{{{a^2+12^2=15^2}}}
Square:
{{{a^2+144=225}}}
Subtract 144 from both sides:
{{{a^2=81}}}
Square Root both sides
{{{a=9}}}
The wall is 9 ft from the ground.