# Question Video: Solving an Equation with One Root by Graphing Mathematics • 9th Grade

The graph in the diagram represents the function π(π₯) = 2π₯ β 7. Without performing any calculation, use the graph to solve 2π₯ β 7 = 0.

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### Video Transcript

The graph in the diagram represents the function π of π₯ equals two π₯ minus seven. Without performing any calculation, use the graph to solve two π₯ minus seven equals zero.

The point at which two π₯ minus seven equals zero is the point where it crosses the π₯-axis, where the π¦-coordinate is equal to zero. In this case, we can see that the function two π₯ minus seven crosses the π₯-axis at 3.5. Therefore, our solution is π₯ equals 3.5.

We could check this by solving the equation two π₯ minus seven equals zero using the balancing method. Adding seven to both sides of our equation gives us two π₯ is equal to seven. And finally, dividing both sides of this equation by two gives us an answer π₯ equals seven divided by two, which is equal to 3.5.