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| Question 462566:  ∠PQR and ∠ABC are complementary angles and ∠PQR is four times as large as ∠ABC. Determine the measure of each angle.
 Answer by math-vortex(648)
      (Show Source): 
You can put this solution on YOUR website! ∠PQR and ∠ABC are complementary angles and ∠PQR is four times as large as ∠ABC. Determine the measure of each angle. ------------------------------------
 A big part of solving this problem is knowing how to translate an English sentence in to algebraic language.
 .
 Let
 x = the measure of ∠PQR
 y = the measure of ∠ABC
 .
 We know that the two angles are complementary. By definition, the sum of their measures is 90 degrees. We can write this as an equation:
 [the measure of ∠PQR] + [the measure of ∠ABC] = 90 degrees
 x + y = 90
 .
 We also know that ∠PQR is four times as large as ∠ABC. Let's translate this into algebraic equation.
 [the measure of ∠PQR] = 4 *  [the measure of ∠ABC]
 y = 4 * x
 y = 4x
 .
 Now we have two equations in two variables. Let's solve for x and y.
 x + y = 90
 y = 4x
 .
 Substitute 4x for y in the first equation, and solve for x.
 x + y = 90
 x + (4x) = 90
 5x = 90
 x = 18
 .
 Substitute 18 for x in the second equation, and solve for y.
 y = 4x
 y = 4(18)
 y = 72
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 We see that the measure of ∠PQR is 18 degrees and and the measure of ∠ABC is 72 degrees.
 18 + 72 = 90, so the two angles are complementary.
 72 = 4(18), so ∠PQR is four times as large as ∠ABC.
 .
 hope this helps!
 .
 Ms.Figgy
 math.in.the.vortex
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