Question

A refrigerator has a volume given by the trinomial y3 + y2 – 56y. What are the possible dimensions of the refrigerator? Use factoring.

A. y, y + 8, and y – 7

B. y, y – 8, and y + 7

C. y + 7, y + 7, and y – 7

D. y + 8, –y + 8, and –y + 7

Answer 1

Hey @XbriX again!

This one looks much like the other.
Only now you can first factor y:

y(y²+y-56) = y(y+a)(y+b)

Now remember what you learned earlier: you are looking for a and b,

with a+b=1 and a*b=-56

What are a and b?

Answer 2

y, y – 8, and y + 7?(:

Answer 3

-8+7=-1 :(
-8*7=-56 :)

So it is 8 and -7...

Answer 4

y, y + 8, and y – 7?

Answer 5

Right!

Answer 6

would u help me with another?


A sphere has a radius of 4x + 4. Which polynomial in standard form best describes the total surface area of the sphere? Use the formula S = 4pir2 for the surface area of a sphere.


A. 64pix2 + 128pix + 64pi
B. 64pix2 – 128pix + 64pi
C. 64pix2 + 128pix – 64pi
D. 64pix2 – 128pix – 64pi

Answer 7

Put the radius in the formula: 4π(4x+4)² and expand...

Answer 8

(first, do (4x+4)², then multiply everything with 4π.

Answer 9

64pix2 + 128pix + 64pi?

Answer 10

Right again!

Answer 11

are you serious? im actually starting to understand it lol. thank you!