To solve the equation [tex]\( A = \frac{e+f}{2} \)[/tex] for [tex]\( e \)[/tex], follow these detailed steps:
1. Start with the given equation:
[tex]\[
A = \frac{e + f}{2}
\][/tex]
2. Eliminate the fraction by multiplying both sides of the equation by 2:
[tex]\[
2A = e + f
\][/tex]
3. Isolate the variable [tex]\( e \)[/tex] by subtracting [tex]\( f \)[/tex] from both sides of the equation:
[tex]\[
2A - f = e
\][/tex]
4. Therefore, the solution for [tex]\( e \)[/tex] is:
[tex]\[
e = 2A - f
\][/tex]
Thus, the expression for [tex]\( e \)[/tex] in terms of [tex]\( A \)[/tex] and [tex]\( f \)[/tex] is:
[tex]\[
e = 2A - f
\][/tex]