Write a quadratic equation that has a y-intercept of 24 and the distance between the x-intercepts is 10. Explain how you arrived at your answer.

Respuesta :

Answer:

  y = x² -14x +24

Step-by-step explanation:

You want a quadratic with x-intercepts that differ by 10 and a y-intercept of 24.

Quadratic

If the roots are p and q, then we require ...

  y = (x -p)(x -q) = x² -(p+q)x +pq

The y-intercept is pq, which the problem requires to be 24. Then p and q will be factors of 24 that differ by 10.

Factoring

The value 24 can be factored as ...

  24 = 1·24 = 2·12 = 3·8 = 4·6

The factor differences are, in order, 23, 10, 5, 2. We want the factors that differ by 10, so we can choose ...

  p = 2, q = 12

and the quadratic is ...

  y = x² -(2 +12)x +24

  y = x² -14x +24 . . . . . . desired quadratic

__

Additional comment

Reflecting the curve across the y-axis will not change the y-intercept or the difference of the roots. That equation would be ...

  y = x² +14x +24

Ver imagen sqdancefan