We know a or b != 0
but a-b==0 so both are the same unknown number
b/a must = 1
so
a/b is equivalent to b/a as a/b=1 as well.
So the last answer choice.
Answer:
General equation of line :
--1
Where m is the slope or unit rate
Table 1)
p d
1 3
2 6
4 12
d = Number of dollars (i.e.y axis)
p = number of pound(i.e. x axis)
First find the slope
First calculate the slope of given points
---A


Substitute values in A
Thus the unit rate is 3 dollars per pound.
So, It matches the box 1 (Refer the attached figure)
Equation 1 : 

Since p is the x coordinate and d is the y coordinate
On Comparing with 1

Thus the unit rate is
dollars per pound
So, It matches the box 2 (Refer the attached figure)
Equation 2 : 

Since p is the x coordinate and d is the y coordinate
On Comparing with 1

Thus the unit rate is 9 dollars per pound
So, It matches the box 3 (Refer the attached figure)
Table 2)
p d
1/9 1
1 9
2 18
d = Number of dollars (i.e.y axis)
p = number of pound(i.e. x axis)


Substitute values in A
Thus the unit rate is 9 dollars per pound
So, It matches the box 3 (Refer the attached figure)
1) 0.4
2)0.875
i dont know the 3 and 4 one
Well A should be congruent to S because (Base Angles Therom)
A =S