I need help with #18 please! there’s a hint if you flip the screen, too :)

x°= 30°, y°= 90°

Step-by-step explanation:

AB is a straight line. Thus, the sum of angles on AB is 180°. The abbreviation for this is (adj. ∠s on a str. line).

Let the point at the center be point E.

∠AEB +∠DEB= 180° (adj. ∠s on a str. line)

(y +x)° +(y -x)°= 180°

y +x +y -x= 180

2y= 180

y= 180 ÷2

y= 90

y°= 90°

∠AEC= ∠DEB (vert. opp. ∠s)

(2x)°= (y -x)°

2x= y -x

2x +x= y

3x= y (simplify)

3x= 90 (subst. y=90)

x= 90 ÷3

x= 30

x°= 30°

c is the answer

step-by-step explanation: