What is the solution to this system of equation in simplified ordered pair form using elimination?

6c-9d=111
5c-9d=103

1 answer

To solve the system of equations using the elimination method, we can start with the following equations:

  1. \( 6c - 9d = 111 \) (Equation 1)
  2. \( 5c - 9d = 103 \) (Equation 2)

We can eliminate \(d\) by subtracting Equation 2 from Equation 1:

\[ (6c - 9d) - (5c - 9d) = 111 - 103 \]

This simplifies to:

\[ 6c - 9d - 5c + 9d = 8 \]

Which further simplifies to:

\[ c = 8 \]

Now that we have the value of \(c\), we can substitute it back into one of the original equations to find \(d\). Let's use Equation 2:

\[ 5c - 9d = 103 \]

Substituting \(c = 8\):

\[ 5(8) - 9d = 103 \] \[ 40 - 9d = 103 \] \[ -9d = 103 - 40 \] \[ -9d = 63 \] \[ d = -\frac{63}{9} \] \[ d = -7 \]

Thus, we have \(c = 8\) and \(d = -7\).

The solution in ordered pair form is:

\[ \boxed{(8, -7)} \]