Question

If (x, -1) is the solution for the following system of equations, solve for the value of x. 5x+5y=103y=x-6

Answer 1

The point (x,-1) is a solution of equation 5x+5y=10 and equation 3y=x-6. This means that point satisfy both the equations.

Substitute -1 for x in equation 5x+5y=10 to obtain the value of x.

$\begin{gathered} 5x+5(-1)=10 \\ 5x-5=10 \\ x=\frac{15}{5} \\ =3 \end{gathered}$

So the point is (3,-1).

To check

Substitute 3 for x and -1 for y in equation 3y=x-6 to verify the result.

$\begin{gathered} 3(-1)=3-6 \\ -3=-3 \end{gathered}$

Since point satisfy the equation 3y=x-6 also.

Hence value of x is 3.