Answer:
r = 15
Step-by-step explanation:
I don't really have an explanation, I'm just good at quick math,
I'm sorry if you wanted an explanation, I would explain but I am really bad at explaining math.
A)
The question tells us that
y + z = 180
And
y=3x+20
z=x
So we put them in the first formula:
y + z = 180
(3x + 20) + x = 180
Add and get x to one side:
4x + 20 = 180
4x + 20 - 20 = 180-20
4x = 160
Divide both sides by 4
x = 40
B)
Put x back in to equation to get size of each angle:
Y =3x +20
Y=3(40)+20
Y=120+20
Y=140
Z=x
Z=40
Verify: y+z=180
140+40=180
180=180
X= 134.60, or if you want the equation, 628.35= 89.95+4x
