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20 votes
3x+7=7x+8-3x how do i solve this? is it like infinite solutions, no solutions (Ø) or an actual number answer?

User Mogzol
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2 Answers

20 votes
20 votes

Answer:

x=-1

Explanation:

3x+7=7x+8-3x

3x+7=4x+8

-4x -4x

-x+7=8

-7 -7

-x=1

-1

x=-1

User Vucko
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2.9k points
15 votes
15 votes

Hey there!

3x + 7 = 7x + 8 - 3x

3x + 7 = 4x + 8

SUBTRACT 4x to BOTH SIDES

3x + 7 - 4x = 4x + 8 - 4x

WORK IT OUT!

NEW EQUATION: -x + 7 = 8

-1x + 7 = 8

SUBTRACT 7 to BOTH SIDES

-1x + 7 - 7 = 8 - 7

CANCEL out: 7 - 7 because it give you 0

KEEP: 8 - 7 because it give you the value of x.

NEW EQUATION: -1x = 8 - 7

SIMPLIFY IT!

-1x = 1

DIVIDE -1 to BOTH SIDES

-1x/-1 = 1/-1

CANCEL out: -1/-1 because it give you 1

KEEP: 1/-1 because it give you the value of x

NEW EQUATION: x = 1/-1

SIMPLIFY IT!

x = -1

Therefore, your answer is: x = -1

Good luck on your assignment and enjoy your day!

~Amphitrite1040:)

User DomingoMG
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2.4k points