How do you multiply matrices? (please show steps)

Abc will undergo two transformations to give aa'b'c' which pair of transformations will give a different image of aabc if the order of the transformations is reversed? a. a rotation 90' counterclockwise about the origin followed by a reflection across the y-axis b a translation 5 units down followed by a translation 4 units to the right c. a reflection across the x-axis followed by a reflection across the y-axis a rotation 180'clockwise about the ongin followed by a reflection across the y-axis reset next 2 omentum all rights reserved o atk me anything o o e