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m∠A = 109°
m∠B = 71°
Since Angles 1 and 2 form a linear pair, the two angles sum up to 180°
m∠1 + m∠2 = 180°
m∠1 = 5x + 9
m∠2 = 3x + 11
Plug in the expressions into the equation above:
(5x + 9) + (3x + 11) = 180°
Combine like terms:
5x + 3x + 9 + 11 = 180°
8x + 20 = 180°
Subtract 20 from both sides:
8x = 160°
Divide both sides by 8:
x = 20°
Substitute in this value of "x" into each equation:
m∠A = 5(20) + 9 = 109°
m∠B = 3(20) + 11 = 71°
