Question

3x-7y=9; x=-2 the value of y is

Answer 1

Given question:

`\begin{gathered} 3x-7y=9 \\ x=-2 \end{gathered}`

To find the value of y, we will follow the steps below

Step 1: make y the subject of the formula

`\begin{gathered} 3x-7y=9 \\ 7y=3x-9 \end{gathered}`

Step 2: substitute the value of x=-2 into the expression above

`\begin{gathered} 7y=3(-2)-9 \\ 7y=-6-9 \\ 7y=-15 \end{gathered}`

Step 3: Divide both sides by 7

`\begin{gathered} (7y)/(7)=-(15)/(7) \\ \\ y=-(15)/(7) \end{gathered}`

Thus, the value of y is:

`-(15)/(7)`