Answer:
Step-by-step explanation:
R=x/7 let's say R is what Ryan earned, and so he earns x dollars every seven days
L=2(R)
L=2(x/7)Let's say L is what Lee earned, she earned twice as much as Ryan so 2(x/7)
Total=2(x/7)+x/7
Total=3(x/7) the total earnings is the sum of x/7 and 2x/7 is 3x/7
Using <span>Descartes' rule of signs.
There are 4 changes of signs of coefficients:
+ to - (+x^6-x^5)
- to + (-x^4+4x^3)
+ to - (+4x^3-12x^2)
- to + (-12x^2+12)
Therefore, there are 4,2 or 0 positive roots </span><span><span>at most</span>. So it must be the third answer.
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There would be 7 dimes and 18 nickels
No because if you plug in 4 for x and 5 for y you get -4 not 36