Question

Solve the equations below. With explanations please.

A. y = -2x – 4
y = 5x + 5

B. -3x + y = 8
2y = 6x – 10

C. 2y = 4(x + 3)
y – 2x = 6
D. x + 2y = 4
4x – 2y = 16

Answer 1

Explanation:

y=-2x-4

y=5x+5

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-2x-4=5x+5

-2x-5x-4=5

-7x-4=5

-7x=5+4

-7x=9

x=9/-7

x=-9/7

y=5(-9/7)+5

y=-45/7+35/7

y=-10/7

Answer: x=-9/7, y=-10/7. (-9/7, -10/7).

----------------------------------------------------

-3x+y=8

2y=6x-10

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6x-2y=10

-3x+y=8

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y=8-(-3x)=8+3x

6x-2(8+3x)=10

6x-16-6x=10

-16=10

no solution

Answer: No Solution

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2y=4(x+3)

y-2x=6

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y=4x+12

y=2x+6

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4x+12=2x+6

4x-2x+12=6

2x+12=6

2x=6-12

2x=-6

x=-6/2

x=-3

y=2(-3)+6=-6+6=0

Answer: x=-3, y=0. (-3, 0).

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x+2y=4

4x-2y=16

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5x=20

x=20/5

x=4

4+2y=4

2y=4-4

2y=0

y=0/2

y=0

Answer: x=4, y=0. (4, 0).