Question

2x+4y-31=123......Solve for y and x

Answer 1

The answer is X=77-2y

Answer 2

Answer:
`y\text{ = }(154-2x)/(4)`

x = 77 - 2y

Explanations:

2x + 4y - 31 = 123

Collect like terms:

Note that when -31 crosses to the right side of the equality sign, it becomes +31

The equation becomes:

2x + 4y = 123 + 31

2x + 4y = 154

2x crosses to the right side of the equality sign and becomes -2x

4y = 154 - 2x

Divide both sides by 4

`\begin{gathered} (4y)/(4)=\text{ }(154-2x)/(4) \\ y\text{ = }(154-2x)/(4) \end{gathered}`

To solve for x:

The given equation is

2x + 4y - 31 = 123

2x + 4y = 123 + 31

2x + 4y = 154

4y crosses the equality sign to the right and becomes -4y:

2x = 154 - 4y

Divide through by 2, the equation becomes:

`\begin{gathered} (2x)/(2)=\text{ }(154)/(2)-(4y)/(2) \\ x\text{ = }77\text{ - 2y} \end{gathered}`