Answer:
see explanation
Explanation:
the sum of the 3 angles in a triangle = 180°
sum the 3 angles and equate to 180
4x + 21 + x - 10 + 2x + 8 = 180
7x + 19 = 180 ( subtract 19 from both sides )
7x = 161 ( divide both sides by 7 )
x = 23
Then angles in triangle are
4x + 21 = 4(23) + 21 = 92 + 21 = 113°
x - 10 = 23 - 10 = 13°
7x + 8 = 7(23) + 8 = 161 + 8 = 169°
the only 2 possible angle measures are A and E