Question

Write the coefficient of y in the expansion of (5-y)2.
5. b) 10. c) -10. d) 1​

Answer 1

Answer:

5 (1-2X)  = 9 (1-X)

5 - 10X = 9 -9X

5-9 = -9X + 10X

-4 = X  

SO, X = -4