Question

Please answer, thanks :)

Answer 1

First, you find the angle inside the triangle on the bottom right. You can do this using the 123°, because angles on a straight line add up to make 180°.

180°-123° = 57°

Angles in a triangle also add up to make 180°. You now have two angles, so can therefore find the third by subtracting those two from 180°.

180°-(57°+42°) = 180°-99°= 81°

Now you can use the same rule as the start to find x (angles on a straight line add to 180°)

180°-81° is going to give you 99° because we have reversed the previous step. When you get more confident with this you can skip steps but for now it’s better to just write it all out.

So x = 99°

Answer 2

The supplement to 123 degrees is 57 degrees.

57 + 42 +(180-x) = 180

x = 57 + 42 = 99

Answer: 99 degrees