Please help ASAP!!!!!!

Mathematics

1 answer:

Usimov [2.4K]2 years ago

8 0

Answer:

x = 10

Step-by-step explanation:

3x - 9 = 21

add 9 on both sides:

⇒ 3x - 9 + 9 = 21 + 9

⇒ 3x = 30

divide 3 on both sides:

⇒ $\frac{3x}{x} = \frac{30}{3}$

⇒ x = 10

to check answer, substitute x by 10 on the original equation:

⇒ 3x - 9 = 21

⇒ 3 x 10 - 9 = 21

⇒30 - 9 = 21

⇒ 21 = 21

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