Is 5 ft , 12 ft, 15 ft , a right triangle or not?

If its less than 90 inches, than yes. Thats a right triangle

If it has a 90 degree angle than yes it is 

HOPE THIS HELPED!

20y5 times 2 is 1010 times -2 is -20, plus y

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.