Answer:
m∡BCA = 57°
Step-by-step explanation:
find 'x' by adding all expressions and setting them equal to 360°
9x+1 + tx+12 + 10x-37 = 360
24x = 384
x = 16
Substitute 16 into 10x-37
160 - 37 = 123
m∡BCA is supplemental with 123°, therefore it measures 57°