Solve the equation in the picture
Multiply by on the right of both sides of , then use the fact that matrix multiplication is associative.
If , then
1, 2, 4, 7, 14, 28. These are all the factors of 28.
The answer is 3!
Exact from is -33/8 but in this equation the answer will be in mixed number form so it will be choice number 3.