The attic floor, abcd in the model, is a square. the beams that support the roof are the edges of a block (rectangular prism) efghklmn. e is the middle of at, f is the middle of bt, g is the middle of ct and h is the middle of dt. all the edges of the pyramid in the model have length 12m.

calculate the length of ef, one of the horizontal edges of the block.

EF = 6m.

Step-by-step explanation:

Given that:

1) All the edges of the pyramid in the model have length 12m.

So, AB = 12m

2) E is the middle of AT, F is the middle of BT

So, EF is a line segment connecting the midpoints of ΔATB

So, by applying The Triangle Mid-segment Theorem

EF // AB and EF = 0.5 AB

So, EF = 0.5 AB = 0.5 * 12 = 6m

The Triangle Mid-segment Theorem:

The line segment connecting the midpoints of any two sides of a triangle has the following properties:

1) The line segment will be parallel to the third side.

2) The length of the line segment will be a half of the length of the third side.

answer: -8.2562234e+13

the simplified form is

step-by-step explanation:

we want to simplify the expression,

let us change the middle bar to a normal division sign to obtain,

we multiply the first fraction by the reciprocal of the second fraction to obtain,

we factor to obtain,

we cancel the common factors to get,

we simplify to get,

the correct answer is b