Correct answer: A

The correct answer is $(x,y)=(3,5)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute $y=x+2$: $2x+x+2=11$. Thus $3x=9$, $x=3$, and $y=5$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: B

The correct answer is $(x,y)=(7,3)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute into the second equation: $2y+1+y=10$. Thus $3y=9$, $y=3$, and $x=7$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: C

The correct answer is $(x,y)=(4,0)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute to get $3x+4-x=12$, so $2x=8$, $x=4$, and $y=0$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: D

The correct answer is $(x,y)=(8,3)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute $x=y+5$: $2(y+5)-y=13$. Thus $y=3$ and $x=8$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: A

The correct answer is $(x,y)=(4,4)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute to get $x+2x-4=8$, so $3x=12$, $x=4$, and $y=4$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: B

The correct answer is $(x,y)=(2,1)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute: $4(3-y)+y=9$, so $12-3y=9$, $y=1$, and $x=2$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: C

The correct answer is $(x,y)=(3,15)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute to get $x+5x=18$, so $x=3$ and $y=15$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: D

The correct answer is $(x,y)=(4,5)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute into the second equation: $2y-6+y=9$. Thus $3y=15$, $y=5$, and $x=4$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: A

The correct answer is $(x,y)=(3,3)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute: $2x-(-x+6)=3$, so $3x=9$, $x=3$, and $y=3$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.

Correct answer: B

The correct answer is $(x,y)=(12,3)$.

1. Choose a system method: Use substitution, elimination, a graph, or an equivalent form that makes one variable easy to determine.
2. Solve for the ordered pair: Substitute to get $4y+y=15$, so $5y=15$, $y=3$, and $x=12$.
3. Check both equations: Substitute the ordered pair into both original equations and verify that it satisfies each one.