Whats the answer & how do i solve it ?

Area of rectangle = 225/2 or 112.5

Step-by-step explanation:

Given,

Consider a rectangle ABCD.

Let AC be a diagonal of rectangle of length   = 15

In triangle  ABC.

Sin 45° =height/hypotenuse   {SinФ = height / hypotenuse}

Here, hypotenuse = diagonal of rectangle ( i.e AC = 15)

And height is AB

Therefore, sin 45° = AB/AC

or sin 45° = AB / 15

or 1/√2 = AB /15

AB = 15/√2

Similarly we can find Base (i.e BC) using cosine.

Cos 45° = Base/Hypotenuse

Cos 45° = BC / AC

or  1/√2 = BC/15

BC = 15/√2

Hence we got length of rectangle , AB= 15/√2

And width of rectangle , BC = 15/√2

Therefore, area of rectangle = Length × Width

Area of rectangle = 15/√2  ×   15/√2  = 225/2

Hence, area of rectangle = 225/2 = 112.5

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this

the highest percentage for deaths in construction from highest to lowest is as follows: falls, struck by objects, electrocution, and caught-in/between. these four are collectively known as fatal four.

in the case of falls, the type that is responsible for the overall highest death in the category is falls from roofs.