Q. ∠1 and ∠2 are vertical angles. If m∠1=(2x+13)∘ and m∠2=(7x+28)∘, then find the measure of ∠2.Answer:
Vertical angles congruent: Vertical angles are congruent, so m/∠1=m/∠2. Set the expressions for m/∠1 and m/∠2 equal to each other to solve for x. (2x+13)=(7x+28)
Set expressions equal: Subtract 2x from both sides to get the x terms on one side.(2x+13)−2x=(7x+28)−2x13=5x+28
Subtract x terms: Subtract 28 from both sides to isolate the x term.13−28=5x+28−28−15=5x
Isolate x term: Divide both sides by 5 to solve for x.−515=55xx=−3
Divide by 5: Now that we have the value of x, substitute it back into the expression for m/angle 2 to find the measure of angle 2.m/angle 2=(7x+28)m/angle 2=(7(−3)+28)
Substitute x value: Calculate the value of m/angle 2.m/angle 2=(−21+28)m/angle 2=7 degrees
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