9+3x=21 what is the answer

Mathematics

1 answer:

taurus [48]4 years ago

3 0

Answer: x = 4

Step-by-step explanation:

Solving

9 + 3x = 21

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

1) Add '-9' to each side of the equation.

9 + -9 + 3x = 21 + -9

2) Combine like terms: 9 + -9 = 0

0 + 3x = 21 + -9

3x = 21 + -9

3) Combine like terms: 21 + -9 = 12

3x = 12

4) Divide each side by '3'.

x = 4

5) Simplifying

x = 4

#BaconSquad

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