Choose the solutions to the quadratic equation x2 – 8x – 9 = 0. –21 –1 9 29

-1 and 9

Step-by-step explanation:

To solve the quadratic, factor and set its factors equal to 0. Factoring is the action of breaking up a polynomial into pieces which multiply to make it. The factors are found by multiplying numbers to make C and add to B of .

Here c = -9 and b = -8. The numbers -9 and 1 multiply to -9 and add to -8. These are the factors (x-9)(x+1).

Set each equal to 0 and solve for x.

x-9 = 0

x = 9

x+1 =0

x = -1

x= cost per bracelet

number of bracelets * x + shipping charge = total cost

so

9x+9=72