Answer:
11.) 10w^2 + 43w + 21.
12.) -15y^2 - 2y + 8
Check the explanation for details
Explanation:
11.) You are meant to multiply each row by both columns. For instance, multiply 5w by 2w and 7 you will get 10 w^2 and 35 w
Also, multiply 3 by both 2w and 7 you will get 6w and 21. Therefore,
Expansion of ( 5w + 3 )( 2w + 7 ) will produce 10w^2 + 37w + 6w + 21
= 10w^2 + 43w + 21.
12.) Repeat the same process by multiplying row by column.
Multiply -3y by 5y and 4 you will get -15y^2 and -12y.
Also, multiply 2 by same 5y and 4. You will get 10y and 8
Therefore, the expansion of
( -3y + 2 )( 5y + 4 ) will be
-15y^2 - 12y + 10y + 8
-15y^2 - 2y + 8