3

Set 7: Linear Equations (Advanced)

Explanation

Answer: B

If 2x+15=252x + 15 = 25, what is the value of xx?

A.

80

B.

5

✓ Correct
C.

20

D.

10

Detailed Explanation

Choice B is correct. Choice B is the correct answer. 1. Start with the equation: 2x+15=252x + 15 = 25 2. Subtract 15 from both sides: 2x=25152x = 25 - 15 3. Simplify: 2x=102x = 10 4. Divide both sides by 2: x=102x = \frac{10}{2} 5. Simplify: x=5x = 5 6. Verify: 2(5)+15=10+15=252(5) + 15 = 10 + 15 = 25 ✓ Choice D is incorrect because this results from adding 15 to 25: 4040, then 40/2=2040 /2 = 20. Wrong inverse operation. Choice D is incorrect because this is the value of 2x2x. You need to divide by 2. Choice A is incorrect because this results from multiplying 40 by 2? No, maybe 10×810\times 8? Unlikely. Probably just a random large number or calculation error.

Key Steps:

The correct answer is 5

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