Andrew M. answered • 07/27/16

Mathematics - Algebra a Specialty / F.I.T. Grad - B.S. w/Honors

The way this problem is written the answer is 8y+5

(5y+4)+(3y+1)

= 5y + 3y + 4 + 1

= 8y + 5

Even if these were meant to be multiplied as in

(5y+4)(3y+1)

it would still not equal to

10y + 12

Your book is incorrect. Typing mistakes such as this do occur.