If you subtract the second equation from the first, what happens to the $y$ terms? Write out the subtraction carefully, including both sides of the equation.

Once you have an equation with only $x$, solve it. Then plug that $x$ value into one of the original equations to find $y$.

Type y = 7 - 3x into Desmos, then on a new line type y = 3 - x. This graphs both equations as straight lines.

Look for the point where the two lines cross. Click or tap on that intersection dot; Desmos will show its coordinates. Those coordinates give the $(x,y)$ pair that satisfies both equations and should match one of the answer choices.

We are given the system:

Notice that the coefficient of $y$ is the same (both are $1$). This makes the elimination method convenient: if we subtract one equation from the other, the $y$ terms will cancel.

Subtract the second equation from the first:

Simplify each side:

• Left side: $3x + y - x - y = 2x$
• Right side: $7 - 3 = 4$

So we get:

Now solve for $x$:

Use either original equation to find $y$. Using the simpler one, $x + y = 3$:

Substitute $x = 2$:

Subtract $2$ from both sides:

So the solution to the system is the ordered pair $(x,y) = (2,1)$, which matches answer choice D.