Many televisions are classified by the length of the diagonal of their screens. a 60 in. television has a screen height of 32 in.

how wide is the television's screen?

35in
68in
28in
51in

Okay 
We know
Height= 32
Diagonal = 60

We Also know a television screen is either a square or rectangle no matter which one, they both can be divided to two triangles. The diagonal remains the same for both triangles and actually all sides has the same measures in both triangles.

Lets use the famous pythagoras formula

K^2+ K ^2 = H^2

So the first K is the Height = 32
The second K we want to find out so it is just K

H will be the Diagonal

So again 32^2+ K^2= 62^2

Now we can solve by

Sorting

1024+ K^2 = 3600

We write the Height and Diagonal as wholenumbers by multiplying 32 with 32 and 60 with 60. 32*32= 1024 and 60*60 = 3600

Now we want K alone

1024 +K^2-1024= 3600-1024

K^2 = 2576

K is still squared we want just K. So Lets find the square root of K. As we say K^2 is the same as 2576 we want to know the square root 2576. That where our answer is

2576 square root= 50,754

So our answer must be 51 inch.

We rounded 50,75 up to 51. This is because The 0,7 has shorter distance to become a 1 than to become a Zero. It has only 0,3 to become 1 while 0,7 to become 0