Respuesta :

Answer:

Step-by-step explanation:

Because you have a parallelogram, the two angles shown are "same side interior angles" which means they add up to 180°.

We would say that they are supplementary (they add up to 180°)

So add them together and set them equal to 180°

(4x+18) + (8x+30) = 180°

This is all adding, so we dont really need any of these parenthesis.

4x+18+8x+30=180

Add the x terms together and add the constants (plain numbers) together.

12x + 48 = 180

Subtract 48 from both sides of the equation.

12x = 132

Divide both sides by 12

x = 11