2) i don't know answer for 2, but i know that it isn't right triangle because from Pythagoras' Theory we know that for right triangle: a^2 + b^2 = c^2 but in this triangle 30^2 + 38^2 ≠ 54^2
3) from Pythagoras' theory we know that the area of the square whose side is the hypotenuse (the side opposite the right angle) is equal to the sum of the areas of the squares on the other two sides: a^2 + b^2 = c^2
we have to check this in this triangle:
12^2 + 16^2 = 400
√400 = 20
we know that third side of this triangle is 20 so this triangle is right triangle
3) in square all sides are same so If a is the one side of the square then area of this square will be a x a = 242
a^2 = 242
so from Pythagoras' theorem we can found the diagonal:
a^2 + a^2 = c^2 ( c is hypothenuse)
242 + 242 = c^2
484 = c^2
c = 22
hope it's correct and it'll help you :)
