Which is not a solution to the equation x -2y = 10 ?
2 answers:
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In cases like these, you simply have to multiply the choices you have for each step.
In fact, you can choose between 4 different crusts. For each of these crusts you can choose 4 different sauces. This means that there are choices at this point. In fact, if we call the crust options 1,2,3,4 and the sauce options A,B,C,D, the 16 possible combinations are
From here, you keep going multiplying the number of options for each step, for a total of
ANSWER: 32 five-dollar bills
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EXPLANATION:
Let x be number of $5 bills
Let y be number of $10 bills
Since we have total of 38 bills, we must have the sum of x and y be 38
x + y = 38 (I)
Since the total amount deposited is $220, we must have the sum of 5x and 10y be 220 (x and y are just the "number of" their respective bills, so we multiply them by their value to get the total value):
5x + 10y = 220 (II)
System of equations:
Divide both sides of equation (II) by 5 so our numbers become smaller
Rearrange (I) to solve for y so that we can substitute into (II)
Substituting this into equation (II) for the y:
We have 32 five-dollar bills
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If we want to finish off the question, use y = 38 - x to figure out number of $10 bills
32 five-dollar bills and 6 ten-dollar bills