Solve the system of equations algebraically.
y = 7x + 15
y = 4x + 9

The solution to system of equations is (x, y) = (-2, 1)

Solution:

Given that we have to solve the system of equations algebrically

Given two equations are:

y = 7x + 15 eqn 1

y = 4x + 9 eqn 2

We can use substitution method to solve the given system of equations

Substitute eqn 2 in eqn 1 and solve for the unknown variable

4x + 9 = 7x + 15

4x - 7x = 15 - 9

-3x = 6

x = -2

Now substitute x = -2 in any one of equations and solve for y

Let us substitute x = -2 in eqn 1

y = 7(-2) + 15

y = -14 + 15

y = 1

Thus the solution to system of equations is (x, y) = (-2, 1)