An equation that matches the graph must be true when you plug in $(80,0)$ and also when you plug in $(0,50)$.

If an equation would give a $y$-intercept of 80 instead of 50 (or an $x$-intercept of 50 instead of 80), it does not match the graph.

Enter the points $(80,0)$ and $(0,50)$ so you can check which equation passes through both.

Enter each answer choice as an equation (for example, type 5x+8y=400). Desmos will graph a line for each equation.

Only one of the graphed lines will pass through both $(80,0)$ and $(0,50)$. Choose the equation whose line matches that requirement.

From the graph, the line crosses the axes at:

• $x$-intercept: $(80,0)$

• $y$-intercept: $(0,50)$

A line with intercepts $a$ and $b$ can be written as

Here, $a=80$ and $b=50$, so

Multiply both sides by 400 (a common multiple of 80 and 50):

which simplifies to $5x+8y=400$.

Therefore, the correct choice is $5x + 8y = 400$.