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Angle A and angle B are complimentary angles. If angle A=x²+40 and angle B=2x+42, what is the measure of each angle?

User Andriy K
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1 Answer

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Answer:

see explanation

Explanation:

complimentary angles , sum to 90° , then

∠ A + ∠ B = 90 ( substitute values )

x² + 40 + 2x + 42 = 90 ( simplify left side )

x² + 2x + 82 = 90 ( subtract 90 from both sides )

x² + 2x - 8 = 0 ← quadratic equation in standard form

(x + 4)(x - 2) = 0 ← in factored form

equate each factor to zero and solve for x

x + 4 = 0 ⇒ x = - 4

x - 2 = 0 ⇒ x = 2

If x = - 4 , then

∠ A = x² + 40 = (- 4)² + 40 = 16 + 40 = 56°

∠ B = 2x + 42 = 2(- 4) + 42 = - 8 + 42 = 34°

the 2 complimentary angles are 56° and 34°

If x = 2 , then

∠ A = 2² + 40 = 4 + 40 = 44°

∠ B = 2(2) + 42 = 4 + 42 = 46°

the 2 complimentary angles are 44° and 46°

User Mornaner
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