SOLUTION: Hi! How do I solve the linear systems using substitution? -2x+4y = 2 y= -6x +20 and y= -4x+8 7x

SOLUTION: Hi! How do I solve the linear systems using substitution? -2x+4y = 2 y= -6x +20 and y= -4x+8 7x - 6y =-17

Question 794785: Hi!
How do I solve the linear systems using substitution?
-2x+4y = 2
y= -6x +20
and
y= -4x+8
7x - 6y =-17
Answer by Cromlix(4381) (Show Source): You can put this solution on YOUR website!
Hi there,
-2x + 4y = 2......1
y = -6x + 20.......2
Substitute (-6x + 20) for
y in Eq(1)
-2x + 4y = 2......1
-2x + 4(-6 + 20) = 2
-2x - 24x + 80 = 2
Collect like terms;
-2x - 24x = 2 - 80
-26x = -78
x = 3
Substitute x = 3 into
Eq (2)
y = -6x + 20.......2
y = -6(3) + 20
y = -18 + 20
y = 2
{3, 2}
..............
y = -4x + 8.......1
7x - 6y = -17.....2
Substitute (-4x + 8) for
y in Eq (2)
7x - 6y = -17.....2
7x -6(-4x + 8)= -17
7x + 24x - 48 = -17
Collect like terms;
7x + 24x = -17 + 48
31x = 31
x = 1
Substitute x = 1 into
Eq(1)
y = -4x + 8.......1
y = -4(1) + 8
y = -4 + 8
y = 4
{1, 4}
Hope this helps.
:-)

RELATED QUESTIONS
How do I slove the following systems of linear equations: 2x + 4y = 22 and y - x = 1... (answered by Alan3354)

Can you please tell me if i got these correct? Im doing a practice test to study for my... (answered by Edwin McCravy,solver91311)

Hi please help me solve this equation:Solving Linear Systems-Solve the linear system... (answered by boilpoil)

how do i do this problem by using substitution 4x+4y=24 y=6x+20 (answered by Alan3354,MathLover1)

Solve the system using the substitution method. Show all your steps. 1. x+2y=6... (answered by checkley79)

how do i do these using substitution? 1. 2x-y=-6 4x+y=-6 2. 2x-y=3 4x-y=-1 (answered by Alan3354)

how to solve a system by substitution? problems: 1) y= 6x + 13 and y= -4x - 17 2) y= (answered by solver91311)

How do I solve this by using substitution? y=2x+3 and... (answered by EdenWolf)

I have a question about linear systems using substitution. How do solve: x=6-4y and... (answered by Alan3354,stanbon)