Question

(16)2 + (21)2 - (13)2 + ? = (25)2​

Answer 1

Answer: 2

Step-by-step explanation:

16×2+21×2-13×2+ a = 25×2

32+42-26+ a = 50

74-26+ a = 50

48+ a = 50

a=50-48

a= 2

Answer 2

Answer:

Let the unknown be 'x'

(16)2 + (21)2 - (13)2 + x = (25)2

32 + 42 - 26 + x = 50

x = 50 - 32 - 42 + 26

x = 18 - 42 + 26

x = - 24 + 26

x = 2