To eliminate a cariable in a system of equations, we multiply the variable by a factor that will make both coefficients of the variable to be equal.
Thus, we multiply the coefficient of y in the second equation by a factor that will make it equal to the coefficient of y in the first equation. i.e. multiply 1/2 by a factor that makes it equal to 3/4. and the factor is 3/2.
Therefore, the third option is the correct answer.
Answer:
15
Step-by-step explanation:
Answer:
64
Step-by-step explanation:
4 cups * 16 quarts = 64 cups
Let x be the amount of cement and y be the amount of sand. If <span>the ratio of cement to sand for mortar is 1:3, then

and y=3x.
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So, if <span>Sandy puts in x=7 shovels of cement, then she puts

shovels of sand.
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Answer: 21 shovels of sand.
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