Can someone please explain to me how to do this?????
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A straight line is 180°, so you can do this:
118 + y = 180
y = 62°
The triangle is an isosceles triangle, so the other angle of the triangle is 62° too.
Now that you have 2 of the 3 angles, you can go find the 3rd angle.
62 + 62 + z = 180
z = 56°
Now you can go find ∠2
56 + ∠2 = 180
∠2 = 124°
124 = 12x + 4
120 = 12x
10 = x