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I need help on this ​

I need help on this ​-example-1
User Lambivist
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1 Answer

10 votes

Answer:

The answer is B.

3x + 5y = 24

4x + 3y = 21

Explanation:

x = cost of a chocolate chip cookie

y = cost of an oatmeal cookie

3x + 5y = 24

4x + 3y = 21

Lets solve:

-3(3x + 5y = 24) ==> -9x - 15y = -72

5(4x + 3y = 21) ==> 20x + 15y = 105

Let's add our new equations:

-9x - 15y = -72

20x + 15y = 105

11x = 33

/11 /11

x = $3.00 (the cost of each chocolate chip cookie)

Now lets find the cost of each oatmeal cookie using one of our original equations: 3x + 5y = 24

3(3) + 5y = 24

9 + 5y = 24

-9 -9

5y = 15

/5 /5

y = $3 (the cost of each oatmeal cookie)

Each type of cookie (chocolate chip and oatmeal), costs $3.00

Hope that helps!

User Eric Zoerner
by
4.8k points