Question

1. 15x - 12° 5x - 18° x = ____ complementary supplementary 15.

Explanation:

Step1: Identify angle - relationship

The two angles are supplementary, so their sum is 180°.
$(15x - 12)+(5x - 18)=180$

Step2: Combine like - terms

$15x+5x-12 - 18 = 180$
$20x-30 = 180$

Step3: Isolate the variable term

Add 30 to both sides of the equation.
$20x=180 + 30$
$20x=210$

Step4: Solve for x

Divide both sides by 20.
$x=\frac{210}{20}=\frac{21}{2}=10.5$

Answer:

$x = 10.5$