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Whitepunk [10]
3 years ago
5

How to find the area of a equilateral triangle that has a perimeter of 21?

Mathematics
1 answer:
Romashka-Z-Leto [24]3 years ago
8 0
First, we have to find the length of each side of triangle. Equilateral triangle means 3 sides r in same length, so each side will be 21 ÷ 3 = 7
Now we need to calculate the height of the triangle. We can do this by Pythagoras theorem
Let the height be h
(7/2)^2 + x^2 = 7^2
The area should be 6.0621778265
Or u can say 6.06 corrected to 3 sig fig
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8 0
2 years ago
The number 42 is increased to 46. what is the percentage by which the number was increased?
Arte-miy333 [17]

Answer:

9.52% ( to 2 dec. places )

Step-by-step explanation:

Calculate the percentage increase using

percent increase = \frac{increase}{original} × 100%

increase = 46 - 42 = 4, hence

percent increase = \frac{4}{42} × 100% ≠ 9.52%


7 0
3 years ago
The value of -7 + 24 ÷ (-3)(2) is _____.<br><br> Show work
densk [106]

Answer:

\boxed{=-23}

Explanation: You had to used pemdas stands for: p-parenthesis, e-exponents, m-multiply, d-divide, a-add, and s-subtracting that came from left to right.

First you had to multiply and divide from left to right.

24/(-3)=-8(2)

8*2=16

-7-16

Then you add and subtract from left to right.

-7-16=-23

=-23

Final answer: \boxed{=-23}

Hope this helps!

And thank you for posting your question at here on brainly, and have a great day.

-Charlie

3 0
3 years ago
______<br> What is 0.142857 as a fraction
Nitella [24]
Start by going in the order of decimals and what ever you end at, put this number on top
142857/<span>100000
And then you simplify it to the smallest numbers and you have your answer. It can't be simplified so it is just:
</span>142857/<span>100000</span>

3 0
3 years ago
Simplify −45(30x−40)+(42x+4) . Write your answer in factored form.
kakasveta [241]

solution

-4(327x-451)

5 0
2 years ago
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