F ( x ) = 7 x + 2
y = 7 x + 2
- 7 x = - y + 2 /*(-1)
7 x = y - 2 / : 7
x = y/7 - 2/7 = ( y - 2 ) / 7
The inverse of the function is:
f^(-1) ( x ) = ( x - 2 ) /7
Given:
The two numbers are


To find:
The highest common factor (HCF) of A and B
Solution:
We have,
...(i)

All the factors of A are prime but the factors of B are not prime. So, it can be written as
...(ii)
From (i) and (ii), it is clear that 3 is the only common factor of A and B. So,

Therefore, the highest common factor (HCF) of A and B is 3.
#8: 14.95+7.55=22.50 so the cost of the DVD is $22.50 and the subtraction equation is, 22.50-7.55=14.95
#10: 2/3+1/3=1 so m=1
#12: 7/9+1/3=10/9 or 1 1/9
Bro be careful with the link