Choice C is the correct answer. We'll use elimination. Let's eliminate y by multiplying the first equation by 2.
Step 1: Multiply the first equation by 2:
2(5x−2y)=2(8)10x−4y=16
Step 2: Add to the second equation:
(10x−4y)+(3x+4y)=16+2613x=42x=1342
This gives non-integer. - First: 5(3)−2(3.5)=15−7=8 ✓
- Second: 3(3)+4(3.5)=9+14=23 eq26
3(3)+4(3.5)=9+14=23
Step 1: Multiply the first equation by 2:
10x−4y=16
Step 2: Add to the second equation:
13x=39x=3
Step 3: Substitute x=3 into the first equation:
5(3)−2y=815−2y=8−2y=−7y=3.5
Solution: (3,3.5)
Verification: 3(3)+4(3.5)=9+14=23 ✓
💡 Strategic Tip: Multiplying to eliminate requires identifying which variable has easier coefficients to match.
Choice A is incorrect because5(4)−2(6)=20−12=8 ✓, but 3(4)+4(6)=36 eq23.
Choice B is incorrect because5(2)−2(1)=10−2=8 ✓, but 3(2)+4(1)=10 eq23.
Choice D is incorrect because5(1)−2(−1.5)=5+3=8 ✓, but 3(1)+4(−1.5)=−3 eq23.