Question

Which set of line segments with the given lengths form a right triangle?

A. 9, 27, 81

B. 10, 24, 26

C. 13, 15, 30

D. 15, 18, 23

Answer 1

FOR PART A.... here... a = 9... b = 27... and c = 81... using phytagoras theorem....
a^2 + b^2 = c^2
9^2 + 27^2 = 81^2
81 + 729 = 6561
810 = 6561 ==> as both sides are not equal.... similarly, do this procedure for the remaining... which side you got as balanced, that will be the right angle triangle sides.... @Secret-Ninja

Answer 2

Wait, so I use this equation, and the number I get... wait, what? I dont understand this...

Answer 3

You actually do not have to do this much calculation. You can always eliminate choices A and C since these 2 fail the basic criteria which is required for a triangle to be possible, i.e. sum of 2 sides should be greater than the third.
Just do what @paki told you for options B and D.

Answer 4

Square each side and check if the largest of the squares is the sum of the squares of other 2.
If this is true, then they form a right angled triangle, else not.

Answer 5

yup this method is also true....

Answer 6

oh i get it now, thanks!

Answer 7

thanks paki but he made it sound easier XD lol

Answer 8

Glad to help. :)
Paki's method was universal though and can be applied always ^^

Answer 9

hmmm always pleasure :-)