I been stuck on this assignment since yesterday and I need some to help explain this to me and provide steps so I can come to the conclusion myself, thank you!

For problems 1-4 solve the given system of equations using either substitution or elimination.

1.{2x+y=-8
{y=2x+4

2.{10x+3y=-11
{8x+2y=-6

3.{-3x+2y=2
{3x+4y=13

4.{4x-y=-y
{-8x+4y=13

5 answers

I will do one:
2x+y=-8
2x+2x+4=-8
4x=-12
x=-3 then y=-6+4=...
you show surprisingly little work, for having been stuck on it (and I presume trying to solve it) for two days.

Still. I'll do one, and maybe you can follow my steps for the others...

#1:
2x+y=-8
y=2x+4

substitution:
The first equation tells you that y = -2x-8
So, substitute that in the second equation, and you now have
-2x-8 = 2x+4
-4x = 12
x = -3
so, y = -2x-8 = -2

elimination. rearrange things a bit so you have
2x + y = -8
-2x + y = 4
Now, if you add the two equations, you eliminate the x, getting:
0x + 2y = -4
y = -2
so, plugging that into the 1st equation,
2x + -2 = -8
x = -3

If you have trouble, come on back, and show how far you got.
1. 2x + y = -8.
y = 2x + 4.
Change Eq2 to standard form:
-2x + y = 4.
Add the Eqs:
2x + y = -8.
-2x + y = 4.
Sum = 0 + 2y = -4,
Y = -2.
In Eq1, replace Y with -2 and solve for X:
2x + (-2) = -8.
X = -3.

2. 10x + 3y = -11.
8x + 2y = -6.
Multiply Eq1 by 2 and Eq2 by 3. Then subtract Eq2 from Eq1:
20x + 6y = -22.
24x + 6y = -18.
Diff. = -4x + 0 = -4.
X = 1.
In Eq1, replace x with 1 and solve for Y:
10*1 + 3y = -11.
Y = -7.

3. -3x + 2y = 2.
3x + 4y = 13.
sum : 0 + 6y = 15.
Y =

4. 4x - y = -y.
-8x + 4y = 13.
In Eq1, solve for X:
4x - y = -y.
4x = y-y,
4x = 0,
X = 0.
In Eq2, replace X with 0 and solve for Y:
-8*0 + 4y = 13.
Y =
B
C
D
D
amongus isn't 100%
B
C
A
D
Those are correct
5/3/2021
12:19 A.M.