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3 years ago

X=-4y 3x+2y=20 Substitution

Mathematics

2 answers:

nadezda [96]3 years ago

7 0

Answer: y= -2; x = 8

Step-by-step explanation:

X=-4y.......equation 1

3x+2y=20......equation 2

Substitute the value of x into equation 2

3 (-4y) + 2y = 20

-12y + 2y = 20

-10y = 20

Divide both sides by -10

y = 20/-10

y = -2

Substitute the value of y into equation 1 to get the value of x

x = - 4(-2)

x = 8

I hope this helps greatly, please mark as brainliest answer.

inysia [295]3 years ago

6 0

Answer:

y=-2

x=8

Step-by-step explanation:

Substitute x=-4y into the other equation:

3(-4y)+2y =20

Multiply out the parenthesis:

-12y +2y = 20

-10y =20

Divide on both sides by -10:

y = 20/-10 =-2

Now, knowing y,you can substite it in the previous equation for x:

x = -4(-2)= 8

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