Question 1191181
.
∠A and \angle B∠B are complementary angles. If m\angle A=(x-21)^{\circ}∠A=(x−21)
∘
and m\angle B=(2x-15)^{\circ}∠B=(2x−15)
∘
, then find the measure of \angle A∠A.
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<pre>
Your equation is


    m(A)   + m(B)    = 90 degrees    (complementary angles)

or
    
    (x-21) + (2x-15) = 90.


Simplify and find x


    x - 21 + 2x - 15 = 90

    x      + 2x      = 90 + 21 + 15

         3x          = 126

          x          = 126/3 = 42.


<U>ANSWER</U>.  m(A) = x-21 = 42-21 = 21  degrees;   m(B) = 2x-15 = 2*42 - 15 = 69 degrees.


<U>CHECK</U>.   m(A) + m(B) = 21 + 69 = 90  degrees.     ! Correct !
</pre>

Solved.


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&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Angles/Angles-basics.lesson>Angles basics</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Angles/Vertical-Angles-.lesson>Vertical angles</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/geometry/How-to-solve-problems-on-suppl-compl-or-vertical-angles-Examples.lesson>HOW TO solve problems on supplementary, complementary or vertical angles - Examples</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Points-lines-and-rays/Solved-problems-on-supplementary-and-complementary-angles-and-pairs-of-angles.lesson>Solved problems on supplementary and complementary angles</A>
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