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4 votes
Slove the system of the linear equations by either sus substitution or elimination 8x-12y=20 4x-4y=-4

2 Answers

4 votes
The first one is 2x - 3y - 5 = 0
The second one is x - y + 1 = 0

The slope intercept form of these would be

The first one is y = 2/3x -5/3
The second one is y = x + 1
User Ducky
by
3.9k points
3 votes

Answer:

x = -8 and y = -7

Explanation:

I will solve your system by substitution.

(You can also solve this system by elimination.)

8x−12y=20;4x−4y=−4

Step: Solve8x−12y=20for x:

8x−12y+12y=20+12y(Add 12y to both sides)

8x=12y+20

8x

8

=

12y+20

8

(Divide both sides by 8)

x=

3

2

y+

5

2

Step: Substitute

3

2

y+

5

2

forxin4x−4y=−4:

4x−4y=−4

4(

3

2

y+

5

2

)−4y=−4

2y+10=−4(Simplify both sides of the equation)

2y+10+−10=−4+−10(Add -10 to both sides)

2y=−14

2y

2

=

−14

2

(Divide both sides by 2)

y=−7

Step: Substitute−7foryinx=

3

2

y+

5

2

:

x=

3

2

y+

5

2

x=

3

2

(−7)+

5

2

x=−8(Simplify both sides of the equation)

User Jomey
by
4.0k points