Home > PC3 > Chapter 4 > Lesson 4.1.2 > Problem 4-29
Consider the polynomial
If you want to determine the factors of
, is a reasonable guess for one of the factors? Explain. Is
a factor of the last term ( )? How can you determine if
is a factor? Can you think of more than one way? Is
a factor of ? Set up the area model with the divisor on the left of the box. Input only the first term of the dividend.
Generic rectangle, 2 rows, 4 columns, left edge labeled, x minus 5, interior top left, labeled x cubed.
Since
divides into , times, write the on top and multiply with the and fill in the area model with the product. Labels added, top edge left, x squared, interior bottom left, negative 5, x squared.
Add an expression to
in order to get the needed . Add it to the right of . Label added, interior top, second from left, 9 x squared.
Dividing
into gives . Add the at the top. Then multiply and and fill the answer in the area model. Labels added: top edge, second from left, + 9 x, interior bottom, second from left, negative 45 x.
Add an expression to
in order to get the needed . Add it to the right of . Label added: interior top, second from right, 34 x.
Dividing
into gives . Add the at the top. Then multiply and and fill the answer in the area model. Labels added: top edge, second from right, + 34, interior bottom, second from right, negative 170.
Add an expression to
in order to get the needed . Add it to the right of . This is the remainder. Labels added: top edge, right, 140 divided by quantity x minus 5. Interior top right, 140.