Multiply your length value by 2.54. One inch is equal to roughly 2.54 centimeters,
Its 20.32 cm btw.
3.4 + 2.7 = 6.1
6.1(5.35) = 32.635
So, you would be charged $32.64 or letter C :)
You can group first two conjunctions and second two:

.
In first brackets you have common

and in second brackets common is 5:

.
and 
use the second expression to calculate the left-hand side of the first equation:

Add 10 to both sides if this equation to get

and divide both sides by 2

this proves that x = 17, give the two initial equations
Answer:
c=-24
Step-by-step explanation:
to find C we have to plug in the coordinate given to us
12(4)+4(-6)+C= 0
48-24+c=0
24+c=0
c=-24