Respuesta :

If you add up all the angles in a triangle it will always be 180.
180 - 45x is angle TRS
Therefore 180 - 45x + 25x + 57 + x = 180
Subtract 180 from both sides
-45x + 25x + 57 + x = 0
Subtract 57 frok both sides
-45x + 25x + x = -57
Combine like terms
-19x = -57
divide both sides by -19 and you get
x = 3

The sum of the angles in a triangle is 180°. It means that when you add up the three angles, you would get 180°.

The angle on a straight line, is also 180°.

Since ∠QRT = 45x, then...

∠TRS = 180° - 45x

So now you add up the angles in the triangle:

(180° - 45x) + 25x + (57 + x) = 180°

Combine like terms:

-19x + 237° = 180°

Subtract 237° to both sides:

-19x = -57

Now, divide both sides by -19:

x = 3