How do you solve for e in #E/e=(R+r)/r#?

1 Answer
Mar 16, 2017

Answer:

#e=(rE)/(R+r)#

Explanation:

Given:#" "E/e=(R+r)/r#

Using first principles:

#color(blue)("YOU CAN DO THIS:"->"Turn everything upside down giving:")#

#color(green)(e/E=r/(R+r))#

Multiply both sides by E

#color(green)(e/Ecolor(red)(xxE)" "=" "r/(R+r)color(red)(xxE))#

#color(green)(e xx(color(red)(E))/E" "=" "(rE)/(R+r)#

But #E/E=1# and #1xxe=e#

#e=(rE)/(R+r)#