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∠A and∠B are vertical angles. If m∠A=(4x+14)° and m∠B=(5x-5)°, then find the measure of∠A .

User Muffy
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Final answer:

To find the measure of angle A, set the expressions for the measures of the vertical angles A and B equal, solve for x, and then substitute back into the expression for angle A. Solving the equation 4x + 14 = 5x - 5 gives x = 19. Substituting x into m∠A = (4x+14)° yields m∠A = 90°.

Step-by-step explanation:

The question involves finding the measure of ∠A when ∠A and ∠B are vertical angles with m∠A being (4x+14)° and m∠B being (5x-5)°.

Vertical angles are congruent, so their measures are equal.

Therefore, we set the expressions for the measures of angles A and B equal to each other to solve for x:

4x + 14 = 5x - 5

Add 5 to both sides:

4x + 19 = 5x

Subtract 4x from both sides:

19 = x

Inserting the value of x into the expression for m∠A:

m∠A = 4(19) + 14

m∠A = 76 + 14

m∠A = 90°.

The measure of ∠A is 90°.

User AmaJayJB
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