SOLUTION: two angles are complementary. the measure of one angle is 21 more than twice the measure of the other angle.find the measure of the angle?

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Question 341238: two angles are complementary. the measure of one angle is 21 more than twice the measure of the other angle.find the measure of the angle?
Found 2 solutions by fractalier, texttutoring:
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
If two angles are complementary, they add to 90.
Thus the angles are x and 90-x (that's tricky, reason it out why it is so)...
Then
(90-x) = 21 + 2x
90 - x = 21 + 2x
Now subtract 21 and add x to both sides in two steps...
69 = 3x
x = 23
90-x = 67

Answer by texttutoring(324) About Me  (Show Source):
You can put this solution on YOUR website!
Complementary means that the angles must add up to 90 degrees.

Let x = first angle
Let y = second angle

Equation 1: y = 2x + 21
Equation 2: x+y = 90

Substitute Eqn 1 into Eqn 2:

x + (2x+21) = 90
3x + 21 = 90
3x = 69
x = 69/3
x = 23
Now you can find the other angle, y:
y = 90-x
y = 90-23
y = 67

So one angle is 23 degrees, and the other angle is 67 degrees.