Question

Statins are used to keep cholesterol in check and are a top-selling drug in the U.S. The equation:
S - 1.3x= 5.2
gives the amount of sales (S) of statin in billions of dollars x years after 1998. According to this
equation, how much will/did people in the U.S. spend on statins in the year 2007?
Answer: People in the U.S. will spend
billion dollars on statins in 2007.

Answer 1

Substituting x=2007-1998=9 we get:

$S-1.3\cdot9=5.2.$

Simplifying the above equation we get:

$S-11.7=5.2.$

Adding 11.7 to the above equation we get:

$\begin{gathered} S-11.7+11.7=5.2+11.7, \\ S=16.9. \end{gathered}$

Answer: People in the U.S. will spend 16.9 billion dollars on statins in 2007.