Question

What is the value of x in the solution to the following system of equations?

x − y = −3
x + 3y = 5

Answer 1

We can rearrange the first equation (x - y = -3) to be

`y = x + 3` (from adding y to both sides then adding 3 to both sides)

we can plug (x + 3) for the y in the second equation
and get

`x + 3(x + 3) = 5`

we can distribute that 3

`x + 3x + 9 = 5`

add like terms

`4x + 9 = 5`

subtract 9 from both sides

`4x = -4`

divide both sides by 4

`x = -1`

therefore your answer would be
`x = -1`