GEOMETRY 3

If 2x-15⁰ and 3x + 35⁰ are complementary angles, find the value of x.

solution

Complementary angles add up to 90⁰.

so,  2x-15⁰ + 3x + 35⁰ = 90⁰.

so,  2x + 3x + 35⁰ - 15⁰ = 90⁰.

so,  5x + 20⁰ = 90⁰.

so,  5x = 90⁰ -  20⁰

so,  5x = 70⁰

so,  5x = 70¹⁴

       5       5

Hence x = 14

TRY THIS...............

If x - 13⁰ and 4x + 73⁰ are complementary angles, find the value of x.