Amir spent RM18 for a bottle of detergent, 2 pencils and 3 light bulbs while Siti spent RM12 for 3 bottles of?
RM12 for 3 bottles of detergent, 2 pencils and a light bulb and Sarah spent RM9 for a
bottle of detergent, 4 pencils and a light bulb. If x, y and z represent the price per unit
for detergents, pencils and light bulbs respectively,
of the form AX = B.
b)find the inverse of marix A by using adjoint matrix
c)determine the price of each item by using the result in b)