When you write URGENT the Brainly cops think you may be taking a test.
y = ax² + c thru (-1,4) and (0,8)
Substituting in the coordinates of each point for x and y gives two equations:
4 = a (-1)² + c
8 = a (0²) + c = c
From the second one we see c=8. Substituting into the first one,
4= a + 8
a = 4-8 = -4
Answer: a=-4, c=8
Check:
f(x) = -4x² + 8
f(0) = 8, good
f(-1) = -4(1) + 8 = 4, good
Answer:
662.6%
Step-by-step explanation:
Answer:
15.98
Step-by-step explanation:
∑₁¹⁰ 
![=8[1+\frac{1}{4} +\frac{1}{16} + ........ +t_{10}]](https://tex.z-dn.net/?f=%3D8%5B1%2B%5Cfrac%7B1%7D%7B4%7D%20%2B%5Cfrac%7B1%7D%7B16%7D%20%2B%20........%20%2Bt_%7B10%7D%5D)
We have to use the formula of sum of a G.P. series with common ratio r < 1.
If the first term is a, the common ratio is r and the number of terms is n then the sum [a + ar + ar² + ar³ + ......... up to n terms] is given by
![[a \times\frac{1-r^{n} }{1-r}]](https://tex.z-dn.net/?f=%5Ba%20%5Ctimes%5Cfrac%7B1-r%5E%7Bn%7D%20%7D%7B1-r%7D%5D)
![= 8[1 \times \frac{1-\frac{1}{2^{10} } }{1-\frac{1}{2} } ]](https://tex.z-dn.net/?f=%3D%208%5B1%20%5Ctimes%20%5Cfrac%7B1-%5Cfrac%7B1%7D%7B2%5E%7B10%7D%20%7D%20%7D%7B1-%5Cfrac%7B1%7D%7B2%7D%20%7D%20%5D)
(Answer)
I got 16.8 , but she’ll need roughly 17 gallons of paint :)
how i did it :
1. so you know she’ll need 4/5 per book case, and there are 16 bookcases.
2. So you do 16 x 5, then you get 84
3. and you divide 84 by 5. and you’ll get 16.8, that’s how many gallons of paint she needs
