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Alex73 [517]
4 years ago
11

Tan20+tan40+tan60+......+tan180=?

Mathematics
1 answer:
Ann [662]4 years ago
8 0
First, notice that \tan180^\circ=0, so the sum is the same as

\tan20^\circ+\tan40^\circ+\cdots+\tan140^\circ+\tan160^\circ

Next, recall the fact that \tan(180^\circ-x)=-\tan x, and notice that

\tan20^\circ=\tan(180^\circ-160^\circ)=-\tan160^\circ
\tan40^\circ=\tan(180^\circ-140^\circ)=-\tan140^\circ

and so on, which means the remaining terms cancel and the value of the sum is 0.
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On a map of South Asia, Nepal looks approximately like a rectangle
Hoochie [10]

Answer:

VK for up ureueusidifdisodaaiwiwu

6 0
3 years ago
Write the equation for a line that passes through the point (-8,2) and is parallel to 5x-4y=4. Enter your equation in slope inte
Lana71 [14]

Answer:

y = 5/4x + 12

Step-by-step explanation:

5x - 4y = 4

-4y = -5x + 4

y = (-5x + 4)/-4

y = 5/4x - 1

Parallel Slope ---> m = 5/4

(-8, 2)

y = mx + b

2 = 5/4(-8) + b

2 = 5 * -2 + b

2 = -10 + b

12 = b

b = 12

y = 5/4x + 12      <---- This is the answer

Hope this helps!

3 0
3 years ago
In a collection of nickels, dimes, and quarters worth $6.90, the ratio of the number of nickels to dimes is 3:8. The ratio of th
dimulka [17.4K]
N=number of nickels
d=number of dimes
q=number of quarters

example
if n:d=3:8
lets say n=3 and d=8
3*8=8*3
so
8n=3d
slightly confusing but go with it, it migh make sense or it might not


n:d=3:8
8n=3d

d:q=4:5
5d=4q

solve for one of them
solve for nickels in first and quarters in second

8n=3d, n=(3/8)d
5d=4q, (4/5)d=q

5n+10d+25q=690
divide by 5 to make it easeir
n+2d+4q=138
sub (3/8)d for n
sub (4/5)d for q
(3/8)d+2d+5(5/4)d=138
(3/8)d+2d+25/4d=138

3/8+2+25/4=
3/8+16/2+50/8=
69/8

(69/8)d=138
times both sides by 8
69d=1104
divide both sides by 69
d=16

16 dimes
sub back

(5/4)d=q
(5/4)16=q
80/4=q
20=q

(3/8)d=n
(3/8)16=n
48/8=n
6=n



6 nickles
16 dimes
20 quarters
yah
8 0
3 years ago
Which list shows these numbers in order from least to greatest​
Rom4ik [11]

Answer:

0.009854, 30%, 1.98, √9

Step-by-step explanation:

Convert to decimals:

0.009854, 1.98, 3.0, 0.3

0.009854, 0.3, 1.98, 3.0

7 0
3 years ago
Reginald answered at 78% of the questions on his social studies quiz correctly what fractional part of the question did he not a
Otrada [13]

If Reginald answered 78% correctly out of a total 100%, we can subtract 78 from 100:

100 - 78 = 22

He answered 22% of the question incorrectly. But how do we find the bottom number? Remember what we said earlier. The <u>total</u> is 100%. He got 22% out of 100% wrong. Wouldn't that be \frac{22}{100}?

Now that we know our fraction, we can reduce it. Let's start by dividing our fraction in half:

\frac{22}{100} = \frac{11}{50}

Can we reduce that any more? No, because 11 can not be divided by anything else.

If you want the first fraction, go with \frac{22}{100}, but if they want a reduced fraction, then \frac{11}{50} would be best.

8 0
3 years ago
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