8
algebra

Determine the number of solutions: {y=5x+210x2y=4\begin{cases} y = 5x + 2 \\ 10x - 2y = -4 \end{cases}

A

No solution

B

Exactly one solution

C

Infinitely many solutions

D

Exactly three solutions

Correct Answer: C

Choice C is the correct answer. Let's rearrange the first equation to compare.

Step 1: Rearrange y=5x+2y = 5x + 2 to standard form: 5x+y=2-5x + y = 2

Multiply by -2: 10x2y=410x - 2y = -4

This is exactly the second equation!

Step 2: Both equations represent the same line → infinitely many solutions

💡 Strategic Tip: Converting between slope-intercept and standard form can reveal identical equations.

Choice A is incorrect because no solution requires parallel lines with different constants.

Choice B is incorrect because one solution requires different slopes.

Choice D is incorrect because linear equations cannot have exactly three solutions.