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2 years ago

. Find the 20th term of the arithmetic sequence 15, 9, 3, -3

Mathematics

1 answer:

vova2212 [387]2 years ago

3 0

Answer:

a20 = -99

Step-by-step explanation:

hello :

the nth term in this arithmetic sequence is : an = a1 + (n -1 )d

a1 = 15 a2 = 9 d = a2-a1 = 9-15 = -6 ( common difrence)

an = 15 + (n -1 )(-6)

an = 15+6-6n

an = -6n+21

the 20th term when n = 20 : a20 = -6(20)+21 = -99

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Two-ninths of the total number of batteries in Richard's desk drawer is made

insens350 [35]

You are told 2/9 = 16

Let total number of batteries = x

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To find x divide both sides by 2/9

X = 72 total batteries

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2 years ago

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For f(x)= x +2 and g(x)= 1/x find (g o f)

lukranit [14]

Hello :
f(x)= x +2 and g(x)= 1/x
(g o f)(x) = g(f(x))=g(x+2) = 1/(x+2)

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2 years ago

– 2y – 10 = x - 10x - y = -14

fredd [130]

Answer:

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Step-by-step explanation:

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2 years ago

nancy spent 7/8 hour working out at the gym she spent 5/7 of that time lifting weights what fraction of an hour did sje spentld

Juli2301 [7.4K]

$\frac{9}{56}\\$ Fraction of hour was spent by NAncy in lifting weights

Step-by-step explanation:

Time spent at the gym by Nancy = $\frac{7}{8}\,hour$

Time spent at lifting weights = $\frac{5}{7}\,hour$

What fraction of hour she spent in lifting weights?

Solving:

Fraction of hour she spent in lifting weights= Time spend at the gym-Time spent at lifting weights

Fraction of hour she spent in lifting weights= $\frac{7}{8}\,hour-\frac{5}{7}\,hour$

$=\frac{49}{56}-\frac{40}{56}\\=\frac{49-40}{56}\\=\frac{9}{56}\\$

So, $\frac{9}{56}\\$ Fraction of hour was spent by Nancy in lifting weights

Keywords: Word Problems involving Fractions

Learn more about Word Problems involving Fractions at:

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7 0

2 years ago

The hypotenuse AB of the right triangle ABC is parallel to the axis of the abscess. Find the length of the hypotenuse if A (-1;

lukranit [14]

Answer:

10.25

Step-by-step explanation:

The slope of AC is given by the slope formula:

m = (y2 -y1)/(x2 -x1)

m = (-4 -1)/(3 -(-1)) = -5/4

Then the slope of CB is the opposite reciprocal, 4/5. The equation of line CB in point-slope form is ...

y -k = m(x -h) . . . . . . line with slope m through point (h, k)

y -(-4) = 4/5(x -3) . . . . line CB

When y = 1 (to match the y-value of A), then ...

1 +4 = 4/5(x -3)

5(5/4) = (x -3) . . . . . multiply by 5/4

6.25 +3 = x = 9.25 . . . . add 3

Point B is (9.25, 1).

The length of the hypotenuse is ...

9.25 -(-1) = 10.25

6 0

1 year ago