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when solving a quadratic equation by graphing, we find the roots using which of the following?

a. vertex

b. x-intercepts

c. y-intercepts

d. none of the above

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Ayanaw H. | Any Mathematics WelcomeAny Mathematics Welcome
5.0 5.0 (589 lesson ratings) (589)

X-Intercept is the value of x where cross x axis.
Another name is the zeros of the function, when y is zero, the graph cross the x-axis
The answer is x-intercepts, Nataliya already answer the question.  I just add some explanations to it.

Parviz F. | Mathematics professor at Community CollegesMathematics professor at Community Colle...
4.8 4.8 (4 lesson ratings) (4)
If  b^2  - 4ac >0
 then find the roots.    if a>0 , then vertex is minimum point
   X vertex  is  half way between roots.
     Roots are ( X1, X2)        X vertex  = ( X1 + ) / 2, Y intercept is always equal c ,
    So having all this information you can plot the curve.
      If  b- 4ac <0 , then there is no X intercept, only find the vertex  Xvertex = -b/2a, and Y intercept = c.
     If a < 0 , then you do the same , the vertex is maximum.  
Nataliya D. | Patient and effective tutor for your most difficult subject.Patient and effective tutor for your mos...

b. x-intercepts