algebra 2 help?

Question

state its solution
x - y = -5
2y = -2 - 2x

A (4, -1)
B (-3, 2)
C (-5, 2)
D (2, 5)
E (-2, -4)
F No Solution

Answer 1

(B)

To solve this sort of system....

(a) place one equation in terms of one of the two variables. Let's place the first equation in terms of x (move everything to the other side):

x - y = -5
x = y - 5

(b) use that value to substitute into the other equation. In this case, we'll replace "x" with "y-5" in the second equation. Then solve the equation, which is now in terms of y only, for y:

2y = -2 - 2x
2y = -2 - 2(y-5)
2y = -2 -2y +10
4y = 8
y = 2

(c) Now that you have y, plug in that value in either original equation to calculate x:

x - y = -5
x - (2) = -5
x = -3

That's the solution. x=-3, y=2, or (-3,2), which is your answer (B).

(d) To check your solution, plug those values into the OTHER equation, whichever one you didn't use in step (c) above:

2y =? -2 - 2x
2*2 =? -2 -2*(-3)
4 =? -2 - (-6)
4 = 4

This is always a good idea, because it helps catch simple mistakes.

Answer 2

First, solve the first equation for x, by adding y to both sides of the equation:
x - y + y = -5 + y
x = y - 5

Next, substitute x of equation 1 (y -5) into the second equation:
2y = -2 -2(y-5)

Distribute -2 into the parenthetical expression:
2y = -2 -2y + 10

Get all the y's on one side of the equation by adding 2y to each side of the equation:
2y + 2y = -2 -2y +10 + 2y
4y = 8

Divide both sides by 4 to get y alone:
y = 2

Now substitute the value for y (in this case, 2) into equation 1 to find x:
x - 2 = -5

Add 2 to both sides of the equation to get x alone:
x - 2 + 2 = -5 + 2
x = -3

So we have x = -3, y = 2, or (-3,2), B.

This is called the substitution method of solving a couple equations.

Answer 3

2x + 2y = -2 Thus x + y = -1
Add this to x - y = -5
So, you get 2x = -6
x = -3
Plugging back into x -y = -5 gives -3 - y = -5 or
y = 2.
If all else fails, just plug in all the options and see if which one works.
The answer is B (-3, 2)

Answer 4

2(x - y = -5)
2x+2y=-2

2x-2y=-10
2x+2y=-2

4x= -12
x= -3

-3-y=-5
-y=-2
y=2

answer is B

Answer 5

Plug in the (x,y) and you will see that B works for the two equations.

Answer 6

first either the absolute value of x+y or (x-y or y-x) must equal five so you are down to A, B, and F

Then just plug and chug The answer is...






















B