The two angles form a straight line which is equal to 180 degrees. This makes the angles supplemtary.
To find x, add the two angles together to equal 180:
7x + x+20 = 180
Combine like terms:
8x + 20 = 180
Subtract 20 from both sides:
8x = 160
Divide both sides by 8:
X = 20
Answer:
x=4
Step-by-step explanation:
"A number" can be rewritten as X:
6x=3x+12
1) subtract 3x on both sides:
3x=12
2) divide both sides by 3:
x=4
Answer:
x = -9/2
Step-by-step explanation:
1. Divide 9 by -1/3:
÷
=
· 
= -27
2. Divide both sides by 2:
2(x - 9) = -27

(x - 9) = 
3. Add 9 to both sides:
x = 
(or 4.5 if you need it in decimal form)
hope this helps!
63 5 tens=50
13 ones=10 and 3 leftover 50+13=63