5

Set 12: Linear Inequalities

Explanation

Answer: A

Find the coordinates of the vertex formed by y=2xy = 2x and x+y=6x + y = 6.

A.

(2,4)(2, 4)

✓ Correct
B.

(3,3)(3, 3)

C.

(1,5)(1, 5)

D.

(4,2)(4, 2)

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Solve the system of equations. 1. Substitute: y=2xy = 2 x into x+y=6x + y = 6 2. Solve: x+(2x)=63x=6x=2x + (2 x) = 6 \rightarrow 3 x = 6 \rightarrow x = 2 3. Find y: y=2(2)=4y = 2(2) = 4 4. Vertex: (2,4)(2, 4) Strategic Tip: Vertices of feasible regions are found by treating inequalities as equations. Choice B is incorrect. Choice C is incorrect. Choice D is incorrect.

Key Steps:

The correct answer is (2,4)(2, 4)

Why others are wrong:
B: Choice B 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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