5
Answer: CSet 12: Systems of Equations (Intermediate)
Explanation
Solve by elimination:
A.
B.
C.
✓ Correct
D.
Detailed Explanation
Choice C is correct. Choice C is the correct answer. We need to multiply both equations to eliminate a variable. Step 1: Multiply first equation by 2 and second by 5: 4x + 10 y = 48$$15x - 10 y = 25 Step 2: Add the equations: $$$19x = 73x = \frac{73}{19}$$ Non-integer. - First: 2(3) + 5(\frac{18}{5}) = 6 + 18 = 243(3) - 2(\frac{18}{5}) = 9 - \frac{36}{5} = \frac{45-36}{5} = \frac{9}{5} \neq 52(2) + 5(4) = 243(2) - 2(4) = -2 \neq \frac{9}{5}2(4) + 5(3.2) = 242(5) + 5(2.8) = 24$ ✓, but substitution in second fails.
Key Steps:
•
The correct answer is
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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