The graph of a system of linear equations is shown.
The solution to the system is . Which choice is the value of ?
For systems shown on a graph, do not try to reconstruct equations unless you have to. Go straight to the intersection point (the only point that satisfies both lines) and then read the requested coordinate carefully: is left-right, and is up-down.
Hints
Find the intersection
Look for the point where the two lines cross.
Use the grid
From the intersection point, trace horizontally to the -axis markings to read the -value.
Coordinate meaning
Remember: in , the second number is the -coordinate.
Desmos Guide
Pick two points on each line
From the graph, choose two clear grid points on Line 1 (for example, and ) and two clear grid points on Line 2 (for example, and ).
Enter both lines in slope-intercept form
Compute each line’s slope from the two points, then write each line as and type both equations into Desmos as two separate expressions.
Find the intersection and read
Click the intersection point of the two graphed lines in Desmos and read the -coordinate shown in the ordered pair.
Step-by-step Explanation
Identify the intersection point
In a graph of a system of two linear equations, the solution is the point where the two lines intersect. From the graph, the lines intersect at .
Read the -coordinate
In an ordered pair , the -coordinate is the second number. For , , so the correct choice is .