## pablobegins 3 years ago Polynomials (Question in image)

1. pablobegins

2. Study23

First, substitute 5 for x in the 2 equations: $$\ \Huge (5)+6; 9(5)+6).$$

3. Study23

4. pablobegins

yes

5. pablobegins

wouldn't it be easier to multiply with x; create the polynomial, then substitute?

6. Study23

Perhaps, but there is less room for error using this method. I'll show you how find the polynomial, as well. Now, the Volume is Height x Width x Length: So the volume is: $\ 8\times11\times51= Volume$

7. pablobegins

Okay..

8. Study23

Now, The Easiest Way to Multiply is to Use a Table, to Foil the two polynomials: |dw:1338768144332:dw|

9. Study23

So, That gives us $$\ \Huge 9x^2+60x+36$$. There's also an $$\ \Huge 8$$, so $$\ \Huge 8(9x^2+60x+36)$$. You can factor a three out of the parenthesis, because 3 is a factor of all three terms. That gives you for a final answer: $$\ \Huge 24(3x^2+20x+12).$$ Did you understand that?

10. Study23

Now, you would substitute 5 in for x, getting your final volume.

11. pablobegins

why 60?

12. pablobegins

oh, i see.

13. pablobegins

awesome, thanks a ton!

14. Study23