Question

7. Solve the following set of equations: 3x - 7y=-4 and 2x - 5y = -3a. (1, 2)b. (2, 1)c. (-2,-1)d. (1, 1)e. (-1,-1)

Answer 1

We will have the following:

First, we solve both expressions for "y", that is:

`\begin{gathered} 3x-7y=-4\Rightarrow-7y=-3x-4 \\ \Rightarrow y=(3)/(7)x+(4)/(7) \\ \\ and \\ \\ 2x-5y=-3\Rightarrow-5y=-2x-3 \\ \Rightarrow y=(2)/(5)x+(3)/(5) \end{gathered}`

Now, we equal both expressions:

`\begin{gathered} (3)/(7)x+(4)/(7)=(2)/(5)x+(3)/(5)\Rightarrow(1)/(35)x=(1)/(35) \\ \\ \Rightarrow x=1 \end{gathered}`

Now, we determine the value of y:

`y=(2)/(5)(1)+(3)/(5)\Rightarrow y=1`

So, the solution is:

`(1,1)`