How do you solve #y=x^2-2x-3# graphically?

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Answer 1 · 2016-09-01T19:50:30

A value of y needs to be given before the graph can be used to solve the equation.

The equation given is the equation for a parabola.

It is a function of x, which means that a value for y can be determined for any chosen value of x.

However, as it is written, it cannot be solved.

If a particular value of "y" is given, then the graph can be used to solve the equation.

For example. Use a graph to solve:

#x^2 -2x -3 =color(red)(0)" "rarr y = 0, "what are the x-values?"#

#x^2 -2x -3 =color(red)(-4)" "rarr y =-4, "what are the x-values?"#

#x^2 -2x -3 =color(red)(7)" "rarr y = 7, "what are the x-values?"#