graphing math and algebra

Question

At the Classic Candy Shoppe, chocolate candies sell for $3.50 an ounce and fruit candies sell for $2.00 an ounce. You buy 8 ounces of candy for $20.50. How many ounces of each type of candy did you purchase?

Once we have our variables, we need to write two equations to model the situation.

Remember:

x = chocolate candies

y = fruit candies

We have two issues to consider:

We have the price per ounce of each type of candy, which when combined with how many ounces of each candy we bought, should equal the total dollar amount so

$3.50(x) + $2(y) = $20.50

We also have the number of ounces of each type of candy we bought

number of ounces of x + the number of ounces of y = 8 ounces so

x + y = 8

she said i can substitution graphing or elimination to figure this out

Answer 1

3.5x + 2 y = 20.5, multiply x+y=8 by 2 and subtract from the 1st equation

2x + 2y = 16

1.5x = 4.5 divide by 1.5

x = 3 chocolate

y= 5 fruit