Question

What is the measurement of

Answer 1

Answer: Angle A = 120° and angle C = 45°

Step-by-step explanation: The first thing to note at the back of our minds is that the sum of the interior angles of a triangle equals 180°. Given that the three angle are available, we can start by adding them all together. Hence,

{12x + 12} + 15 + {3x + 18} = 180

12x + 12 + 15 + 3x + 18 = 180

By collecting like terms, we arrive at,

12x + 3x + 12 + 15 + 18 = 180

15x + 45 = 180

Subtract 45 from both sides of the equation

15x = 135

Divide both sides of the equation by 15

x = 9

At this point, we can now substitute for the value of x = 9 in the expressions representing angles A and C.

Angle A = 12x + 12

= 12(9) + 12

= 108 + 12

= 120

Angle A = 120°

Angle C = 3x + 18

= 3(9) + 18

= 27 + 18

= 45

Angle C = 45°