Answer:
X = 12
<B = 45°
Explanation:
From the diagram above:
Alternate exterior angles are equal. Therefore,
[tex]5x - 15 = 2x + 21 \\ collecting \: liketerms \\ 5x - 2x = 21 \: + 15 \\ 3x = 36 \\ dividing \: bothsides \: by \: 3 \\ \frac{3x}{3} = \frac{36}{3} \\ x = 12 [/tex]
For the measure of angle B
2x + 21°
2(12) + 21 = 24 + 21 = 45
Measure of angle B = 45°
