Question 2 - Figure it out - Page 149 - Chapter 6 Class 8 - We Distribute yet things Multiply (Ganita Prakash)

Transcript

Question 2 Express 100 as the difference of two squares.Difference of two squares means a2 – b2 So, we need to do 100 = a2 – b2 And, find a & b Now, 100 = a2 – b2 100 = (a + b) (a – b) We can write 100 as 50 × 2 50 × 2 = (a + b) (a – b) Thus, a + b = 50 a – b = 2 Note: a + b = 2, a – b = 50 is not possible as sum of two positive numbers should be greater than their difference Now, adding both equations (a + b) + (a – b) = 50 + 2 2a = 52 a = 52/2 a = 26 Putting a = 26 in 1st equation a + b = 50 26 + b = 50 b = 50 – 26 b = 24 Thus, 100 = 262 – 242 Check 262 – 242 = 676 – 576 = 100 Thus, our answer is correct: 100 = 262 – 242