Question

Statins are used to keep cholesterol in check and are a top-selling drug in the U.S. The equation:

Answer 1

People in the U.S spend 18.8 billion dollars in 2009.

What is substituting ?

Substituting in mathematics is putting a specific value in an independent variable to observe a system.

According to the given data

Statins is the top selling drug in US to keep cholesterol in check.

The equation of the sales (S) of statin in billons of dollars x years after is

S - 1.3x = 4.5

The year difference is (2009 - 1998) = 11 years or x = 11

Putting the value of x in the given equation

S - 1.3(11) = 4.5

S = 4.5 + 14.3

S= 18.8

∴ The number of sales of statin is $18.8 billions.

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