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3 years ago

15

How do you solve this equation, 5s^2-14s-3=0

1 answer:

elena55 [62]3 years ago

7 0

It's a quadratic equation. Solve it through factorisation.

5s^2 - 14s - 3 = 0
(5s + 1)(s - 3) = 0

5s + 1 = 0
or
s - 3 = 0

Therefore

s = -1/5
or
s = 3

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pentagon [3]

Answer:

cant see picture but it is an easy question based on equilateral that has 3 identical angles and is congruent. A Scalene has odd sides and is not congruent and an isosceles has two sides identical. You can also get two type of right angled triangle only 45 45 plus 90 for right angle would be be congruent

Step-by-step explanation:

3 0

2 years ago

Determine formula of the nth term 2, 6, 12 20 30,42

nalin [4]

Check the forward differences of the sequence.

If $\{a_n\} = \{2,6,12,20,30,42,\ldots\}$ , then let $\{b_n\}$ be the sequence of first-order differences of $\{a_n\}$ . That is, for n ≥ 1,

$b_n = a_{n+1} - a_n$

so that $\{b_n\} = \{4, 6, 8, 10, 12, \ldots\}$ .

Let $\{c_n\}$ be the sequence of differences of $\{b_n\}$ ,

$c_n = b_{n+1} - b_n$

and we see that this is a constant sequence, $\{c_n\} = \{2, 2, 2, 2, \ldots\}$ . In other words, $\{b_n\}$ is an arithmetic sequence with common difference between terms of 2. That is,

$2 = b_{n+1} - b_n \implies b_{n+1} = b_n + 2$

and we can solve for $b_n$ in terms of $b_1=4$ :

$b_{n+1} = b_n + 2$

$b_{n+1} = (b_{n-1}+2) + 2 = b_{n-1} + 2\times2$

$b_{n+1} = (b_{n-2}+2) + 2\times2 = b_{n-2} + 3\times2$

and so on down to

$b_{n+1} = b_1 + 2n \implies b_{n+1} = 2n + 4 \implies b_n = 2(n-1)+4 = 2(n + 1)$

We solve for $a_n$ in the same way.

$2(n+1) = a_{n+1} - a_n \implies a_{n+1} = a_n + 2(n + 1)$

Then

$a_{n+1} = (a_{n-1} + 2n) + 2(n+1) \\ ~~~~~~~= a_{n-1} + 2 ((n+1) + n)$

$a_{n+1} = (a_{n-2} + 2(n-1)) + 2((n+1)+n) \\ ~~~~~~~ = a_{n-2} + 2 ((n+1) + n + (n-1))$

$a_{n+1} = (a_{n-3} + 2(n-2)) + 2((n+1)+n+(n-1)) \\ ~~~~~~~= a_{n-3} + 2 ((n+1) + n + (n-1) + (n-2))$

and so on down to

$a_{n+1} = a_1 + 2 \displaystyle \sum_{k=2}^{n+1} k = 2 + 2 \times \frac{n(n+3)}2$

$\implies a_{n+1} = n^2 + 3n + 2 \implies \boxed{a_n = n^2 + n}$

6 0

2 years ago

Four equivalent expressions of 32+48

Misha Larkins [42]

32+48 = 80

Four equivalent expressions are:

40+40 = 80

20+60 = 80

10+70 = 80

30+50 = 80

4 0

3 years ago

A 33 gram sample of a substance that's

Mazyrski [523]

9514 1404 393

Answer:

6.2

Step-by-step explanation:

We presume your "k-value" is the k in the exponential decay term ...

e^(-kt) . . . where t is the number of time units

This is 1/2 when ...

ln(1/2) = -kt

t = ln(1/2)/(-k) = ln(2)/k

t = 0.69315/0.1124 ≈ 6.2

The half life is about 6.2 time units.

6 0

2 years ago

Suppose your friend's parents invest $25000 in an account paying 7% compounded annually. What will the balance be after 8 years?

oksano4ka [1.4K]

200,000 that’s the answer

7 0

3 years ago