A goldsmith combined an alloy that costs $4.20 per ounce with an alloy that costs $1.70 per ounce. How many ounces of each were used to make a mixture of 200 oz costing $2.40 per ounce?

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so:

answer: -2+√x,-2-√x

i hope this , i don't know if you're looking for a pair or not.

first one because it can't have a fraction in it

step-by-step explanation: