Question

Unknown angle problems (with algebra)

Answer 1

Answer:

x = 20

Step-by-step explanation:

100 + 3x + x = 180

100 + 4x = 180

- 100          -100

4x = 80

÷4   ÷4

x = 20

360° is a full circle, and since this is half you set the numbers equal to 180°

I hope this helps!