Answer:
∠A = 99°
Explanation:
Complementary angles sum to 180°, thus
∠A + ∠B = 180 ← substitute values
2x - 23 + x + 20 = 180
3x - 3 = 180 ( add 3 to both sides )
3x = 183 ( divide both sides by 3 )
x = 61
Hence
∠A = 2x - 23 = (2 × 61) - 23 = 122 - 23 = 99°