-y=x

Question

9x-7y=-16
Solve by substitution

Answer 1

To solve the system of equations using substitution, we start with the two equations:

1. $-y=x$
2. $9x-7y=-16$

First, we will solve the first equation for $y$: $$y=-x$$

Next, we substitute this expression for $y$ in the second equation: $$9x-7(-x)=-16$$

This simplifies to: $$9x+7x=-16$$

Combining like terms gives: $$16x=-16$$

Now, we solve for $x$: $$x=\frac{-16}{16}=-1$$

With $x=-1$, we now substitute this value back into the equation $y=-x$ to find $y$: $$y=-(-1)=1$$

Thus, the solution to the system of equations is: $$(x,y)=(-1,1)$$

The solution is: $$\boxed{{\displaystyle (-1,1)}}$$