Question

Suppose ∠A and ∠B are complementary angles, m∠A = (3x + 5)°, and

Answer 1

M∠A + m∠B = 90

$(3x + 5) + (2x - 15) = 90$

$(3x + 2x) + (5 - 15) = 90$

$5x - 10 = 90$

$5x - 10 +10 = 90+10$

$5x = 100$

$5x/5 = 100/5$      $Divide \ both \ sides \ by \ 5$

$x = 20$                 $Solutions$

m∠A = $3x + 5$     $(x=20)$

m∠A = $3(20) + 5$          $Substitute \ x \ for \ 20$

m∠A = $60 + 5$               $Simplify$

m∠A = $65$


m∠B = $2x - 15$

m∠B = $2(20) - 15$

m∠B = $40 - 15$

m∠B = $25$

Answer 2

         m∠A + m∠B = 90
(3x + 5) + (2x - 15) = 90
(3x + 2x) + (5 - 15) = 90
                  5x - 10 = 90
                      + 10  + 10
                         5x = 100
                          5      5
                           x = 20

m∠A = 3x + 5
m∠A = 3(20) + 5
m∠A = 60 + 5
m∠A = 65

m∠B = 2x - 15
m∠B = 2(20) - 15
m∠B = 40 - 15
m∠B = 25