How do you solve this?

x=25°, y=10°

Step-by-step explanation:

∠A+∠B=180°

8y+10y=180°

18y=180°

y=10°

∠B+∠C=180°

10y+4x-20°=180°

10*10°+4x=180°+20° (y=10°)

100°+4x=200°

4x=200°-100°

4x=100°

x=25°

H̲̅ᴇ̲̅ʏ̲̅!̲̅ L̲̅ᴇ̲̅ᴛ̲̅'̲̅s̲̅ ɢ̲̅ᴇ̲̅ᴛ̲̅ ʜ̲̅ᴇ̲̅ʟ̲̅ᴘ̲̅ɪ̲̅ɴ̲̅ɢ̲̅.̲̅

To do this, we're going to follow the good old trick of the process of elimination. A number can't be irrational if it doesn't end/doesn't repeat.

a. -0.3 is rational because it ends.
b.  is irrrational because it results to about 1.732, then it keeps going on without repeating.
c. 1/3 is rational because it repeats.
d. 0.13 (repeating) is rational becuase it repeats.

The answer is b.

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