SOLUTION: • Post a response to the following: If you are looking at a graph of a quadratic equation y = ax2 + bx + c, how do you determine where the solutions to 0 = ax2 + bx + c are? Compar
Question 477801: • Post a response to the following: If you are looking at a graph of a quadratic equation y = ax2 + bx + c, how do you determine where the solutions to 0 = ax2 + bx + c are? Compare this with solving the equation using the quadratic formula. Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website! it's when the graph crosses the x-axis.
that gives you the value of x when y is equal to 0.
the graph will show you the approximate value of x.
the quadratic formula will give you the exact value of x.
the only reason the graph gives you the approximate value of x is because the resolution of the graph is usually not fine enough to pinpoint the exact value.
here's an example:
equation is 5x^2 + 3x - 13 = 0
here's the graph.
you can see the approximate locations of the roots.
they are somewhere around x = -2 and x = 1
the detail isn't fine enough to pinpoint them exactly though.
the quadratic formula gets you to the exact solution
using that formula, you get:
x = -1.940121947
x = 1.340121947
the roots of the quadratic are the value of x when the value of y is equal to 0.
