Solve using substitution. y=-10x-7 y=-9x-6 square square politician 1)

To solve the system of equations using substitution, follow these steps:<br /><br />Given:<br />\[ y = -10x - 7 \]<br />\[ y = -9x - 6 \]<br /><br />Since both equations are equal to \( y \), set them equal to each other:<br />\[ -10x - 7 = -9x - 6 \]<br /><br />Solve for \( x \):<br />\[ -10x + 9x = -6 + 7 \]<br />\[ -x = 1 \]<br />\[ x = -1 \]<br /><br />Now substitute \( x = -1 \) back into one of the original equations to find \( y \). We'll use the first equation:<br />\[ y = -10(-1) - 7 \]<br />\[ y = 10 - 7 \]<br />\[ y = 3 \]<br /><br />So, the solution to the system of equations is:<br />\[ x = -1 \]<br />\[ y = 3 \]<br /><br />Therefore, the solution is:<br />\[ (x, y) = (-1, 3) \]