Answer:
x=7
Step-by-step explanation:
3(2x - 5) = 9(10 - x)
6x-15=90-9x
6x+9x=90+15
15x=105
x=7
Answer:
Amy: 8, Ben: 3
Step-by-step explanation:
No explanation here
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
