Solve by elimination: -6x+3y=-4
-20x+10y=20

i know the answer is no solution, but i need to know why.

Ok, there's no solution because of the like term grouping

Step-by-step explanation:

For eg;2w+3x+4w will be equal to

6w+3x which is a like term grouping. So only if there are like terms, there will be a solution.

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