After you eliminate $x$ by adding the equations, you will get a simple equation in terms of $y$. Solve that equation to find $y$.

Once you know $y$, plug it into either original equation and simplify carefully. Pay attention: you only need the value of $5x$, not $x$.

In Desmos, type the two equations exactly as they are, each on its own line:

• 5x - 2y = 11
• -5x + 7y = 9 Desmos will graph both lines.

Click on the point where the two lines intersect. Desmos will display the coordinates $(x, y)$ of this intersection, which is the solution to the system.

In a new expression line, type 5 * ( followed by the $x$-coordinate of the intersection, then ). The output is the value of $5x$ you need to choose from the answer options.

Notice the $5x$ in the first equation and the $-5x$ in the second:

If you add the two equations, the $5x$ and $-5x$ terms cancel out. This is the elimination method.

Add the left sides and the right sides:

Combine like terms:

• $5x + (-5x) = 0$
• $-2y + 7y = 5y$

So you get

Now solve for $y$:

Substitute $y = 4$ into one of the original equations, for example $5x - 2y = 11$:

Compute $-2(4)$:

Now isolate $5x$ by adding 8 to both sides:

The problem asks for the value of $5x$, not $x$ itself. From the previous step, evaluate $11 + 8 = 19$, so $5x = 19$. The correct choice is 19.