This is the answers from MathPapa
<u>Answer</u>
8√2
<u>Explanation</u>
Simply: 4√2 + 7√2 - 3√2
Let √2 = x
4√2 + 7√2 - 3√2 = 4x + 7x - 3x
= 11x - 3x
= 8x
Substituting x with √2
4√2 + 7√2 - 3√2 = 8√2
I think it is reasonable. She will have extra cash (almost $500) but that isn't a bad thing when you are going on a vacation.
If you need to know how to do it, what I did was take the $48 and the 52 weeks and multiply them together to get $2,496.... But if you think in your own opinion it's not reasonable than say she could trim down her savings and only try to earn about 40 dollars each week; you get to the closer amount of $2,000 with $2,080...
I hope this helps. Choose for yourself though! <3 Good luck! (:
That is the vertex form of a quadratic equation
The nth term of the geometric sequence is:
an=ar^(n-1)
where
a=first term
r=common ratio
n=nth term
from the question:
120=ar(3-1)
120=ar^2
a=120/(r^2)....i
also:
76.8=ar^(5-1)
76.8=ar^4
a=76.8/r^4.....i
thus from i and ii
120/r^2=76.8/r^4
from above we can have:
120=76.8/r²
120r²=76.8
r²=76.8/120
r²=0.64
r=√0.64
r=0.8
hence:
a=120/(0.64)=187.5
therefore the formula for the series will be:
an=187.5r^0.8