Answer:
because SRC is the outer angle of the triangle STR
=> SRC = STR + TSR
<=> 101 = 4x + 12 + 7x + 12
<=> 101 = 11x + 24
=> 11x = 77
<=> x = 7
7
Step-by-step explanation:
➝4x+12+7x+12=101°
➝4x+7x+12+12=101°
➝11x+24=101°
➝11x=101-24
➝11x=77
➝x=77/11
➝x=7
