A trigomometry question

A triangle ABC where AB = AC = 24cm abd BC = 14cm. Find the altitude of the isosceles triangle.

Well an Isosceles triangle is just two Right triangles put together. So you have two right triangles with a hypotenuse of 24 and a base of 7. Now just use the Pythagorean Theorem (a²+b²=c²). C is the hypotenuse. So 24²=576, 7²=49, 576-49=527. Now 527 is the altitude SQUARED, so we still have to take the square root of that to get hour answer. The answer is 22.95648056649799, but you should just round up to 23.