Question

Given: x + 2y = -6.

Solve for y. Given: x + y = 6. If x {-15, -6, -1}, then which of the following sets of ordered pairs are solutions?

A.(-15, -21), (-6,-12), (-1,-7)

B.(-15,21), (-6,12), (-1,7)

C. (-15,21), (-6,12), (-1,-7)

Answer 1

Solution of x+2y=-6, y=-3-x/2
Answer B for the correct ordered pairs.

Answer 2

1.
`y=(-6-x)/(2)`

2.B.(-15,21), (-6,12), (-1,7)

Explanation:

In order to solve for Y the first equation you just have to clear the Y from one side of the equation, and we just do it by steps:

`x + 2y = -6.\\x + 2y + (-x)= -6+ (-x)\\(2y)/(2)=(-6-x)/(2) \\y=(-6-x)/(2)`

First you add in both sides of the equation a -x to eliminate the X on the Y side of the equation, and then you divide both sides of the equation by 2, to eliminate the 2 from the Y side of the equation, and now you have you equation solved for Y.

To calculate which pair od solutions are correct, you just have to input the values for X into the equation:

`x+y=6\\(-15)+y=6\\y=6+15\\y=21`

So our first pair would be (-15,21)

`x+y=6\\(-6)+y=6\\y=6+6\\y=12`

So our second pair would be (-6,12)

`x+y=6\\(-1)+y=6\\y=6+1\\y=7`

So our third pair would be (-1,7), and the answer is option "B".