A 25-foot ladder is leaning against a building. The foot of the ladder is 15 feet from the base of the building. How high is the top of the ladder along the building?

20 feet

Step-by-step explanation:

Use the Pythagorean Theorem.

Formula: a^2 + b^2 = c^2

a is the length, and b is the height, and c is the longest edge of the triangle. In this case, you need to find b, the height. Plug in the numbers and solve:

15^2 + b^2 = 25^2

225 + b^2 = 625

-225             -225

b^2 = 400

Take the square root of b to get b by itself, and do the same to the other side of the equation.

The square root of b equals b;

The square root of 400 equals 20.

a) 7x=7

step-by-step explanation: