Answer:
choose 2 friends from 22 friends, we have 231 options
Step One
Figure out the cost for 1 cartridge
Cost = 90
<u>Refund = 8 Subtract</u>
Net cost = 82
Step Two
Find the cost for 14
14 * 82 = 1148 <<<<<< Cost for 14
<u>ANSWER</u>
![\sqrt[3]{- 729{a}^{9} {b}^{6} } = - 9 {a}^{3} {b}^{2}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B-%20729%7Ba%7D%5E%7B9%7D%20%20%7Bb%7D%5E%7B6%7D%20%7D%20%20%3D%20%20-%209%20%7Ba%7D%5E%7B3%7D%20%7Bb%7D%5E%7B2%7D%20)
<u>EXPLANATION</u>
We want to find the cube root of

We express this symbolically as:
![\sqrt[3]{- 729 {a}^{9} {b}^{6} }](https://tex.z-dn.net/?f=%20%5Csqrt%5B3%5D%7B-%20729%20%7Ba%7D%5E%7B9%7D%20%20%7Bb%7D%5E%7B6%7D%20%7D%20)
The expression under the radical called the radicand.
We need to express this radical in exponential form using the property,
![{x}^{ \frac{m}{n} } = \sqrt[n]{ {x}^{m} }](https://tex.z-dn.net/?f=%20%7Bx%7D%5E%7B%20%5Cfrac%7Bm%7D%7Bn%7D%20%7D%20%20%3D%20%20%5Csqrt%5Bn%5D%7B%20%7Bx%7D%5E%7Bm%7D%20%7D%20)
Applying this rule gives us:
![\sqrt[3]{- 729 {a}^{9} {b}^{6} } = ({- 729 {a}^{9} {b}^{6}})^{ \frac{1}{3} }](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B-%20729%20%7Ba%7D%5E%7B9%7D%20%20%7Bb%7D%5E%7B6%7D%20%7D%20%20%3D%20%20%28%7B-%20729%20%7Ba%7D%5E%7B9%7D%20%20%7Bb%7D%5E%7B6%7D%7D%29%5E%7B%20%5Cfrac%7B1%7D%7B3%7D%20%7D%20)
![\sqrt[3]{- 729{a}^{9} {b}^{6} } = ({- {9}^{3} {a}^{9} {b}^{6}})^{ \frac{1}{3} }](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B-%20729%7Ba%7D%5E%7B9%7D%20%20%7Bb%7D%5E%7B6%7D%20%7D%20%20%3D%20%20%28%7B-%20%7B9%7D%5E%7B3%7D%20%20%7Ba%7D%5E%7B9%7D%20%20%7Bb%7D%5E%7B6%7D%7D%29%5E%7B%20%5Cfrac%7B1%7D%7B3%7D%20%7D%20)
Recall that

We apply this rule on the RHS to get,
![\sqrt[3]{- 729{a}^{9} {b}^{6} } = ({- {9}^{3 \times { \frac{1}{3} } } {a}^{9 \times { \frac{1}{3} } } {b}^{6 \times { \frac{1}{3} } }})](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B-%20729%7Ba%7D%5E%7B9%7D%20%20%7Bb%7D%5E%7B6%7D%20%7D%20%20%3D%20%20%28%7B-%20%7B9%7D%5E%7B3%20%5Ctimes%20%7B%20%5Cfrac%7B1%7D%7B3%7D%20%7D%20%7D%20%20%7Ba%7D%5E%7B9%20%5Ctimes%20%7B%20%5Cfrac%7B1%7D%7B3%7D%20%7D%20%7D%20%20%7Bb%7D%5E%7B6%20%5Ctimes%20%7B%20%5Cfrac%7B1%7D%7B3%7D%20%7D%20%7D%7D%29)
This simplifies to
![\sqrt[3]{- 729{a}^{9} {b}^{6} } = - 9 {a}^{3} {b}^{2}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B-%20729%7Ba%7D%5E%7B9%7D%20%20%7Bb%7D%5E%7B6%7D%20%7D%20%20%3D%20%20-%209%20%7Ba%7D%5E%7B3%7D%20%7Bb%7D%5E%7B2%7D%20)
gg easy
the legs of a triangle are related as
wehre a, b, and c are the legs and the hypotonuse of a triangle respectively
let's find some stuff
one easy way is to find a rational value for c find values of a and b
lets pick c=5


now split up 25 into 2 things that don't have rational square roots
if we say
and
then we get
and
(which are both irrational)