English...because english subject is a part of our language worldwide and that can communicate all over the world...its just my opinion
B the set of input values for the function.
Answer:
The equation of straight line is x = 1
Step-by-step explanation:
<u>Step </u>:-
The equation of straight line having slope 'm' and passing through the point
is 
Slope of horizontal line(that is x-axis) is m = 0
slope of vertical line (that is y-axis) is m is not defined
The equation of straight line having slope is not defined and passing through the point (1,7).

cross multiplication we will get equation

x-1 = 0
The equation of straight line is x = 1
Answer:
r= RE/I
Step-by-step explanation:
E=I(R+r)
divide both sides by I
E/I = R+r
subtract both sides by R
R(E/I) = r
r = RE/I