Question

what is the value of x?
○ x = 32
○ x = 36
○ x = 37
○ x = 40
(x + 15)° x° (4x - 20)°

Explanation:

Step1: Use exterior - angle property

The exterior - angle of a triangle is equal to the sum of the two non - adjacent interior angles. So, $(x + 15)+x=4x - 20$.

Step2: Simplify the left - hand side

Combine like terms on the left - hand side: $2x+15 = 4x - 20$.

Step3: Move variables to one side

Subtract $2x$ from both sides: $15=4x - 2x-20$, which simplifies to $15 = 2x-20$.

Step4: Isolate the variable term

Add 20 to both sides: $15 + 20=2x$, so $35 = 2x$.

Step5: Solve for x

Divide both sides by 2: $x=\frac{35}{2}=37$.

Answer:

$x = 37$