Question

ZA and ZB are complementary. If m ZA = (x - 6) º
and m2B = (3x) °, find the value of x.

Answer 1

x=24

Explanation:

If angles are complementary, that means they will add to 90 degrees. We know that ∠A and ∠B are complementary, therefore,

∠A+∠B=90

∠A is equal to x-6, and ∠B is equal to 3x.

x-6+3x=90

Combine like terms (all the terms with variables)

(x+3x)-6=90

4x-6=90

To solve the equation, we want to find out what x is. In order to do this, we have to get x by itself. Perform the opposite of what is being done to the equation. Keep in mind, everything done to one side, has to be done to the other.

6 is being subtracted from 4x. The opposite of subtraction is addition, so add 6 to both sides.

4x-6+6=90+6

4x=90+6

4x=96

x is being multiplied by 4. The opposite of multiplication is division, so divide both sides by 4.

4x/4=96/4

x=96/4

x=24

Answer 2

x = 21°

Explanation:

Complementary angles have a sum of 90°. If ∠A + ∠B = 90°, we know that

x - 6° + 3x = 90°.

4x - 6° = 90°

4x = 96°

x = 24°

Hope this helps!