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3 years ago

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How do you work this out?

1 answer:

Katarina [22]3 years ago

5 0

Because ABCD is a rectangle, the length of CD is 12 cm.

We need to determine the length of DE. If we can do that, then the sum of the lengths of CD and DE represents the unknown: the length of CE.

To find the length of CE, we have to "solve" the upper triangle.

Here's an outline of what to do:

1. Show that BC=AD and find the length.
2. Note that angle CAD is 60 degrees. Why?
3. Note that angle EAD is 30 degrees. Why?
4. Find the length of ED
5. Add ED and DC, that is, ED + 12 cm. This is your answer.

Please ask questions if need be.

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SIZIF [17.4K]

Answer:

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Step-by-step explanation:

Given:

The given equation is.

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Find the some of cube.

Solution:

$8x^{3} +125=0$

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$(2x)^{3} +5^{3}=0$ ----------(1)

The sum of the cube formula is given below.

$(a^{3} +b^{3})=(a+b)(a^{2} -ab+b^{2} )$ -----------(2)

By comparing equation 1 and equation 2

$a=2x, b=5$

substitute a and b value in equation 2

$((2x)^{3} +5^{3})=(2x+5)((2x)^{2} -(2x)(5)+5^{2})$

$((2x)^{3} +5^{3})=(2x+5)(4x^{2} -(10x)+25)$

$((2x)^{3} +5^{3})=(2x+5)(4x^{2} -10x+25)$

Therefore the sum of the cube $(2x+5)(4x^{2} -10x+25)=0$

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3 years ago

A North American river otter wants to cross the North Saskatchewan river. It can swim at a speed of 2.75 m/s. In that location,

insens350 [35]

Answer:

Step-by-step explanation:

time to cross will be the distance divided by the velocity in that direction.

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As velocity is a vector, An observer on the bank would see the velocity as the vector addition of the cross stream and down stream velocities

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natta225 [31]

Answer:

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Step-by-step explanation:

using the law of indices

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