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Algebra Difficulty 3.3 AMC 10/12 Find the answer

One solution of the binary linear equation 2x+y=62x+y=6 is ( ).

A: {  x=2y=2\left\{\begin{array}{l}{\;x=2}\\{y=2}\end{array}\right.

B: {x=1y=3\left\{\begin{array}{l}{x=1}\\{y=3}\end{array}\right.

C: {x=2y=4\left\{\begin{array}{l}{x=2}\\{y=4}\end{array}\right.

D: {x=3y=3\left\{\begin{array}{l}{x=3}\\{y=3}\end{array}\right.

This was a multiple-choice question, but the options didn't survive into the source we have. The answer given is A, and the solution below works it through.

Solution

To solve the binary linear equation 2x+y=62x+y=6 and find the correct solution among the given options, we substitute each option into the equation and check for equality.

Option A: {x=2y=2\left\{\begin{array}{l}{x=2}\\{y=2}\end{array}\right.

Substituting x=2x=2 and y=2y=2 into the equation, we get:
2×2+2=4+2=62 \times 2 + 2 = 4 + 2 = 6
Since the left side of the equation equals the right side (6=66=6), option A satisfies the condition.

Option B: {x=1y=3\left\{\begin{array}{l}{x=1}\\{y=3}\end{array}\right.

Substituting x=1x=1 and y=3y=3 into the equation, we get:
2×1+3=2+3=52 \times 1 + 3 = 2 + 3 = 5
Since the left side of the equation (55) does not equal the right side (66), option B does not satisfy the condition.

Option C: {x=2y=4\left\{\begin{array}{l}{x=2}\\{y=4}\end{array}\right.

Substituting x=2x=2 and y=4y=4 into the equation, we get:
2×2+4=4+4=82 \times 2 + 4 = 4 + 4 = 8
Since the left side of the equation (88) does not equal the right side (66), option C does not satisfy the condition.

Option D: {x=3y=3\left\{\begin{array}{l}{x=3}\\{y=3}\end{array}\right.

Substituting x=3x=3 and y=3y=3 into the equation, we get:
2×3+3=6+3=92 \times 3 + 3 = 6 + 3 = 9
Since the left side of the equation (99) does not equal the right side (66), option D does not satisfy the condition.

Therefore, the correct solution is option A, which satisfies the given binary linear equation 2x+y=62x+y=6.

Thus, the answer is: A\boxed{A}.

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.