Solve the system by substitution.
y = -10x + 9
2x - 10y = 12
First, let's solve the first equation for y:
y = -10x + 9
Next, we substitute this value of y into the second equation:
2x - 10(-10x + 9) = 12
Simplifying the equation:
2x + 100x - 90 = 12
102x - 90 = 12
102x = 102
x = 1
Now that we have the value of x, we can substitute it back into the first equation to find y:
y = -10(1) + 9
y = -10 + 9
y = -1
Therefore, the solution to the system of equations is x = 1 and y = -1.