I got 65/153 since you actually multiply by the reciprocal of the second fraction.
The price for red paper = 1.25
the price for foil = 2.5
rewrite the equation set = to 0.
x^2 + 5x - 8 = 0
The quadratic will not factor so you have to use the quadratic formula.
x = (-b + - sqrt(b^2 - 4ac))/2a
x = (5 + - sqrt(25 - 4* 1* -8))/2
x = (5 + - sqrt 57)/2
The x2is not the same as 2x. It is x^2. X tot he second power which makes the problem a quadratic equation. You cannot combine the terms x^2 and -5x because they so not have the same power.
Joan received $17 and 94 cents ($17.94)
$14.20 + $7.86= $22.06 (her total)
$20+$20= $40 (how much she paid with)
$40- $22.06= $17.94