Answer:
r is the common ratio (in geometric sequence)
d is the common difference (in arithmetic sequence)
n is the term number
a1 is the value of the first term
an is the value of the nth term
Step-by-step explanation:
arithmetic sequence formula:
an=a1+d(n-1)
geometric sequence formula:
an=a1•(r)^(n-1)
Answer:
Parents from the four ESO courses attend a school assembly. A quarter of the parents are from 1st ESO, a tenth are from 2nd ESO, a quarter are from 3rd ESO and 56 parents are from 4th ESO. a) How many parents attended the assembly? b) How many parents from 1ºESO attended the assembly? c) How many parents of 2nd ESO attended the assembly? d) How many 3rd grade parents attended the assembly?
Step-by-step explanation:
Answer: 7
Step-by-step explanation:
The dimensions of the prism can be 2x, 2x+3 and x+6.
We first factor out the GCF of the trinomial. The GCF of the coefficients is 2. Each term has an x in common as well, so the GCF is 2x.
Factoring out the 2x, we have
2x(2x²+15x+18).
To factor the remaining trinomial, we find factors of 2*18=36 that sum to 15. 12*3 = 36 and 12+3 = 15. We split up 15x into 12x and 3x:
2x(2x²+12x+3x+18)
Now we group together the first two terms in parentheses and the last two:
2x((2x²+12x)+(3x+18))
Factor out the GCF of the first group:
2x(2x(x+6)+(3x+18))
Factor out the GCF of the second group:
2x(2x(x+6)+3(x+6))
Factoring out what these have in common,
2x(x+6)(2x+3)
surface area of cylinder = 2 π r h + 2π r²
plug in values of pi, radius and area
2,461.76 = 2× 3.14 × 14 × h + 2× 3.14 × 14 × 14
2,461.76 = 87.92 h + 1,230.88
2,461.76 – 1,230.88 = 87.92h
1,230.88 = 87.92h
1,230.88 ÷ 87.92 = h
h = 14 ft