Answer:
B
Step-by-step explanation:
∠ BSR + ∠ TSB = ∠ TSR , substitute values
2x + 17 + 5x + 15 = 102 , that is
7x + 32 = 102 ( subtract 32 from both sides )
7x = 70 ( divide both sides by 7 )
x = 10 → B
