Question

A=a+b+c+d . Solve for c

Answer 1

A = a + b + c + d

c = A - a - b - d

Answer 2

A-a-b-d =c

Explanation:

A=a+b+c+d

We want to get c alone

Subtract a from each side

A-a = a+b+c+d -a

A-a = b+c+d

Subtract b from each side

A-a -b = b+c+d-b

A-a -b = c+d

Subtract d from each side

A-a-b-d = c+d-d

A-a-b-d =c