10

Set 13: Systems of Equations (Advanced)

Explanation

Answer: C

For what values of kk does the system have no solution? {y=4x3y=kx+5\begin{cases} y = 4x - 3 \\ y = kx + 5 \end{cases}

A.

k=3k = -3

B.

k=5k = 5

C.

k=4k = 4

✓ Correct
D.

k=4k = -4

Detailed Explanation

Choice C is correct. Choice C is the correct answer. For no solution, we need parallel lines. Analysis: - First line: slope = 4, y-intercept = -3 - Second line: slope = kk, y-intercept = 5 Condition for parallel lines (no solution): - Same slope: k=4k = 4 - Different y-intercepts: 35-3 \neq 5 ✓ (already different) With k=4k = 4, the lines are parallel and never intersect. Strategic Tip: In slope-intercept form, equal slopes with different intercepts = no solution. Choice A is incorrect because k=3k = -3 means different slopes (4 and -3), giving one solution. Choice B is incorrect because k=5k = 5 means different slopes, giving one solution. Choice D is incorrect because k=4k = -4 means different slopes, giving one solution.

Key Steps:

The correct answer is k=4k = 4

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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