-18 – (-63) = 45 To evaluate a determinant, take the product of the elements on the main diagonal and subtract the products of the off-diagonal elements. Using Cramer's Rule, the solution to the system of equations ax + by = e, cx + dy = f is x = Det(e,f)/Det(a,b,c,d) and y = Det(a,e)/Det(a,b,c,d). The solution to the given system is (-1,2).

2. Find the value of

3. Find the value of
-18 – (-63)

4. Evaluate
Step 1 Rewrite the first 2 columns to the right of
the determinant.

5. Step 2 Find the product of the elements of
the diagonals.
1 0 12 Sum: 13
9 0 –4 Sum: 5
5 – 13 = -8

6. Find the value of the determinant
4 -6 0 Sum: -2
3 0 4 Sum: 7
7 – (-2) = 9

7. Cramer’s Rule
The solution to the system of equations ax + by = e
cx + dy = f is

8. Use Cramer’s Rule to solve the system of equations.
Answer: (–1, 2)
x
y

9. Use Cramer’s Rule to solve the system of equations.
The solution
is (4, 2)