To make t the subject is basically isolating t
S = at + bt
We see on the right side that t is common, so we factor it out.
S = t(a + b)
Divide by (a+b) to isolate t
\(\frac{S}{a + b} = \frac{t(a+b)}{(a+b)}\)
a + b and a + b cancels out
We are left with the answer:
t = \(\frac{S}{a+b}\)
