If x/2 + y/3 = 4 and x/2 - y/6 = 1, what is the value of y?

Linear and Quadratic Equations · Question 22 of 66

Question 22

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If $\frac{x}{2} + \frac{y}{3} = 4$ and $\frac{x}{2} - \frac{y}{6} = 1$ , what is the value of $y$ ?

2Correct answerYour answer4Correct answerYour answer6Correct answerYour answer18Correct answerYour answer

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CorrectNot quiteAnswer C

Correct answer: C

Multiply the first equation by 6: $3x + 2y = 24$ . Multiply the second by 6: $3x - y = 6$ .
Subtract: $3y = 18$ , so $y = 6$ .
Then $3x = 24 - 12 = 12$ , so $x = 4$ .

Worth noting

4 is $x$ and 18 is $3y$ . Clearing the fractions first turns this into an ordinary elimination.

Ten questions from Linear and Quadratic Equations, at your own pace.

Ten questions from Linear and Quadratic Equations, at your own pace.