Question

Need help, not sure if I got the correct answer.

Answer 1

The length of the ladder is 15 feet.

Solution:

Let the length of the ladder be x.

Distance from ground to the top of the ladder = x – 3

Distance from the bottom of the ladder to the building = 9 feet

To find the length of the ladder:

Using Pythagoras theorem,

$\text{Base}^2+\text{Height}^2=\text{Hypotenuse}^2$

$9^2+(x-3)^2=x^2$

$81+x^2-6x+9=x^2$

$x^2-6x+90=x^2$

Subtract $x^2$ from both sides of the equation, we get

$-6x+90=0$

Subtract 90 from both sides of the equation.

–6x = –90

Divide by –6 on both sides of the equation.

x = 15

Hence the length of the ladder is 15 feet.