How do you multiply (y+7)(y+4)?
Answers
Multiplication of algebric expressions occurs in a series of steps.
Actually, whatever is there, everything should be included in your multiplication, and nothing should be left. This will be our checkpoint.
Now, according to the question, we will proceed our solution and we will see the way to multiply.
(y+7) (y+4)
= (y×y) + (y×4) + (7×y) + (7×4)
= y² + 4y + 7y + 28
= y² + 11y + 28
On back verification, you will see :
y² + 11y + 28
= y² + (4+7)y + 28
= y² + 4y + 7y + 28
= y(y+4) + 7(y+4)
= (y+4) (y+7), which is your above mentioned question.
As a result, it can be verified too after calculation.
Moreover, if your multiplication is correct, i.e., if your calculation is all right, then no need to verify like this. At the primary stage of learning, you can surely verify your answer.