Which of the following triplets are Pythagorean?
(i) (1, 1, 1) (ii) (2, 2, 3)
[We know that the three natural numbers m, n, p are said to be Pythagorean triplets if m² + n² = p².]

5 Write down the correct number in each box:
(a) 65² = 6 x 7(100) + 5² = 4200 + 25 =_________
(b) 75² = 7 x 8(100) + 5² = 5600 + 25 =__________ 6 Which of the following triplets are Pythagorean?
(i) (1, 2, 3) (ii) (3, 4, 5) (iii) (6, 8, 10)
[We know that the three natural numbers m, n, p are said to be Pythagorean triplets if m² + n² = p².] 8 Observe a pattern in the following and find the missing numbers:
22²
121 = _______
1+2+1
(333)²
12321 =_________
1+2+3+2+1
1234321 =__________
123454321 =__________
12345654321 =__________
1234567654321 =__________
123456787654321=___________
(999999999)²
12345678987654321 = ___________________________________
1+2+3+4+5+6+7+8+9+8+7+6+5+4+3+2+1 9 Use calculator to find the squares of all natural numbers between 80 and 90.