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2 years ago

The following picture is a square pyramid where DE=8 cm and m∠ADE=60°.

Mathematics

1 answer:

mr_godi [17]2 years ago

5 0

Answer:

131 cm

Step-by-step explanation:

formula for surface area of pyramid is

S = (1/3)Bh

but the base ia a square, so B = $x^{2}$

S = (1/3) $x^{2} h$

the pic shows h = 8

but we don't know x

do SohCahToa

sin60 = x/8

x = 8sin60

x = 6.92820323 or 7

plug in numbers

S = (1/3) $7^{2}$ 8

S = 392/3

S = 130.6666667 or 131 cm

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No. She needs at least 31 yards of material.

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3 years ago

What is the area in terms of pi

svetoff [14.1K]

Answer:

Step-by-step explanation:

The perimeter of the given figure is equal to the circumference of whole circle.

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$C=\pi d$

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2 years ago

Marcy can walk 12 blocks in 5 minutes. If each block is 50 feet long, how many feet will she walk during the 30 minutes that she

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2 years ago

Read 2 more answers

Simplify<br> 21x^6 y^5<br> 14x^2y^9

PIT_PIT [208]

Answer:

$\frac{3x^{4} }{2y^{4} }$

Step-by-step explanation:

Factor out 7 from top and bottom :

$\frac{7(3x^6y^5)}{7(2x^2y^9)}$

Divide top and bottom by 7 :

$\frac{3x^6y^5}{2x^2y^9}$

Simplify :

$\frac{x^6}{x^4}=x^{2}$

Simplify :

$\frac{y^5}{y^9} = y^{-4} = \frac{1}{y^{4} }$

Collect everything together :

$\frac{3x^{4} }{2y^{4} }$

Hope this helped and have a good day

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1 year ago

students were grouped into 4 classrooms with an average of 33.5 students per classroom. if the students were regrouped into 5 cl

erma4kov [3.2K]

Answer:

26.8

Step-by-step explanation:

Because 33.5 was the average of how many students were in a classroom (if there were 4 classrooms), then 33.5 is can somewhat be the average of how many students were in one classroom; 1/4 of the classrooms can hold an average of 33.5.

Total students that were divided into 4 classrooms :

33.5 × 4 = 134

So if there is 134 students that will be grouped into 5 different classrooms, divide 134 by 5 to find the average amount of students that will be grouped.

134 ÷ 5 = 26.8

So, the average amount of students that will be grouped if they were divided into 5 classrooms would be 26.8 .

Hope this helped !

4 0

1 year ago