Question

two buildings are 20m and 25m high. If the building are 12m apart, find the distance between their tops.

Answer 1

This forms a right-angled triangle-- one side is the length between the buildings, one side is the extra height of one building, and the remaining side is the distance between rooftops. This last side is the hypotenuse. To find the hypotenuse of a right-angled triangle, use Pythagoras' Theorem:  

a^2+b^2 = c^2  

where a and b are the shorter sides.  

'a' is the distance apart,  

'b' is the difference in height, 25m-20m = 5m  

12^2 + 5^2 = c^2  

144 + 25 = c^2  

169 = c^2  

√169 = c^2  

13 = c  

c = 13

Answer 2

so, in this question we have to find the hypotenuse.
therefore,(x^2)=(12^2+5^2)
=(144+25)
x^2 =(169)
x=13