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The equations were multiplied by constants and added together to determine that the value of x in the system of equations is –4. Negative three-fourths x minus two-thirds y = negative 1 One-half x minus five-sixths y = negative 7 What is the value of y? a. –6 b. –3 c. 3 d. 6

User Mathilde
by
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2 Answers

5 votes

Answer:

D. 6

Explanation:

it is right

User Bouramas
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4.9k points
6 votes

Answer:

Option d. 6

Explanation:

we have


-(3)/(4)x-(2)/(3)y=-1 ----> equation A


(1)/(2)x-(5)/(6)y=-7 -----> equation B

Multiply the equation A by -5/4 both sides


(-(5)/(4))(-(3)/(4)x)+(-(5)/(4))(-(2)/(3)y)=-1(-(5)/(4))


((15)/(16))x+((10)/(12)y)=(5)/(4)


(15)/(16)x+(5)/(6)y=(5)/(4) -----> equation C

Adds equation B and equation C


(1)/(2)x-(5)/(6)y=-7\\\\(15)/(16)x+(5)/(6)y=(5)/(4)\\\\-------------\\\\(1)/(2)x+(15)/(16)x=-7+(5)/(4)\\\\(23)/(16)x=-(23)/(4)\\\\x=-4

Find the value of y

substitute the value of x in equation A


-(3)/(4)(-4)-(2)/(3)y=-1


(2)/(3)y=4\\\\y=6

User Delsa
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