Solve using substitution. 6x+y=7 10x+7y=-15 square square

To solve the system of equations using substitution, we can solve one equation for one variable and then substitute that expression into the other equation.

Let's solve the first equation for y:
$$6x + y = 7$$
$$y = 7 - 6x$$

Now we can substitute this expression for y into the second equation:
$$10x + 7y = -15$$
$$10x + 7(7 - 6x) = -15$$
$$10x + 49 - 42x = -15$$
$$-32x + 49 = -15$$
$$-32x = -64$$
$$x = 2$$

Now that we have found the value of x, we can substitute it back into the expression for y:
$$y = 7 - 6x$$
$$y = 7 - 6(2)$$
$$y = 7 - 12$$
$$y = -5$$

Therefore, the solution to the system of equations is $$x = 2$$ and $$y = -5$$ .