7. Find the Value of x. SHOW YOUR WORK OR NO CREDIT!!!!!

Answer:
x=21.9317121994
Step-by-step explanation:
You just look at the half triangle and use the Pythagorean Theorem. One side of the triangle is 9 (half of 18), the other is 20, so you find the hypotenuse.
9²+20²=x²
81+400=x²
481=x²
√481=x
x=21.9317121994