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2 votes
Which equation has exactly one solution?

A. 10x - 3x + 20 + 45 = 100 + 7x - 3
B. 4x - 3x = 10(3 - x) + 11x
C. 10x - 20 + 45 = 19 + 7x + 3(2 + x)
D. 9(x - 3) + 28 = 4x - 3

User Gowiem
by
5.1k points

2 Answers

7 votes

Answer:

the correct answer is D. 9(x-30) + 28 = 4x - 3

Explanation:

User Pablouche
by
4.8k points
1 vote

Answer:

The answer is D

Explanation:

9(x + -3) + 28 = 4x + -3

Reorder the terms:

9(-3 + x) + 28 = 4x + -3

(-3 * 9 + x * 9) + 28 = 4x + -3

(-27 + 9x) + 28 = 4x + -3

Reorder the terms:

-27 + 28 + 9x = 4x + -3

Combine like terms: -27 + 28 = 1

1 + 9x = 4x + -3

Reorder the terms:

1 + 9x = -3 + 4x

Solving

1 + 9x = -3 + 4x

Solving for variable 'x'.

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

Add '-4x' to each side of the equation.

1 + 9x + -4x = -3 + 4x + -4x

Combine like terms: 9x + -4x = 5x

1 + 5x = -3 + 4x + -4x

Combine like terms: 4x + -4x = 0

1 + 5x = -3 + 0

1 + 5x = -3

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

1 + -1 + 5x = -3 + -1

Combine like terms: 1 + -1 = 0

0 + 5x = -3 + -1

5x = -3 + -1

Combine like terms: -3 + -1 = -4

5x = -4

Divide each side by '5'.

x = -0.8

Simplifying

x = -0.8

User Anders Juul
by
5.1k points