Geometry. What is the answer and how do I solve? Please don't waste my answers. I will mark brainliest.

Answer:
QS = 16
Step-by-step explanation:
We can find QS by using the Pythagorean Theorem for Δ SQT
ST = 24/2 or 12
QT = 20
QS² + 12² = 20²
QS² + 124 = 400
QS² = 256
QS = √256, which is 16