Question

what is st? st =

Explanation:

Step1: Identify congruent triangles

Since $\angle SR T=\angle QR T$, $\angle SRT+\angle S = 90^{\circ}$, $\angle QRT+\angle QTR = 90^{\circ}$, then $\angle S=\angle QTR$. Also, $\angle SRT=\angle QRT$ and $RT$ is common. So, $\triangle SRT\cong\triangle QRT$ (by Angle - Angle - Side congruence criterion).

Step2: Use congruence property

For congruent triangles $\triangle SRT$ and $\triangle QRT$, corresponding sides are equal. So, $ST = QT$. Given $QT = 48$, then $ST=48$.

Answer:

48