SOLUTION: Two angles are complementary. The measure of ∠ABC is x° and the measure of ∠DBC is (3x + 10)°. What is the value of x?

Algebra ->  Angles -> SOLUTION: Two angles are complementary. The measure of ∠ABC is x° and the measure of ∠DBC is (3x + 10)°. What is the value of x?       Log On


   

Question 1083600: Two angles are complementary. The measure of ∠ABC is x° and the measure of ∠DBC is (3x + 10)°. What is the value of x?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Answer: 20

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Explanation:

The angles are complementary meaning that they must add to 90 degrees.
If you placed them side by side (adjacent) then they would form a right angle.

(measure of angle ABC) + (measure of angle DBC) = 90 degrees
(x) + (3x+10) = 90
x+3x+10 = 90
4x+10 = 90
4x+10-10 = 90-10
4x = 80
4x/4 = 80/4
x = 20

Check:
(x) + (3x+10) = 90
(20) + (3*20+10) = 90
20+3*20+10 = 90
20+60+10 = 90
80+10 = 90
90 = 90
The last equation is true so x = 20 has been confirmed as the solution.