1

Set 13: Linear Equations

Explanation

Answer: C

If x25=4\frac{x}{2} - 5 = 4, what is the value of xx?

A.

-2

B.

4.5

C.

18

✓ Correct
D.

9

Detailed Explanation

Choice C is correct. Choice C is the correct answer. 1. Start with the equation: x25=4\frac{x}{2} - 5 = 4 2. Add 5 to both sides: x2=4+5\frac{x}{2} = 4 + 5 3. Simplify: x2=9\frac{x}{2} = 9 4. Multiply both sides by 2: x=9×2x = 9 \times 2 5. Simplify: x=18x = 18 6. Verify: 1825=95=4\frac{18}{2} - 5 = 9 - 5 = 4 ✓ Choice C is incorrect because this results from subtracting 5 from 4: 1-1, then multiplying by 2: 2-2. Wrong inverse operation. Choice D is incorrect because this is the value of x2\frac{x}{2}. You must multiply by 2. Choice D is incorrect because this results from dividing 9 by 2: 4.55. We need to multiply.

Key Steps:

The correct answer is 18

Why others are wrong:
A: Choice A is incorrect and may result from a calculation error.
B: Choice B is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

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