Arectangular box is 8 1/2 inches long 5 1/4 inches wide and 4 inches high. what is it’s volume?

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b

the answer is y < -3 or   y > 3

-3y > 7 + 2

-3 y > 9

y < -3