Answer:
A is the answer
Step-by-step explanation:
Answer:
let required no be x

by doing crisscrossed multiplication

42=7x
dividing both side by 7

6=x
therefore x=6
therefore value of remaining no.is 6
Answer:
Step-by-step explanation:
Binomial Expansion:

Pascal's Triangle:
Zero row 1
First row 1 1
Second row 1 2 1
Third row 1 3 3 1
Fourth row 1 4 6 4 1
K + 77 = 2k - (16 - 89)
k + 77 = 2k - (-73)
k + 77 = 2k + (73)
k - 2k = 73 - 77
change the signs
k = 4