Given:
y = 10.2x + 12.6
Where x is the number of years after 2013.
Let's find the number of years which it will take the spending to be more than $84 billion.
We have the inequality:
84 < 10.2x + 12.6
Let's solve for x.
• Subtract 12.6 from both sides:
84 - 12.6 < 10.2x + 12.6 - 12.6
71.4 < 10.2x
• Divide both sides by 10.2:
[tex]\begin{gathered} \frac{71.4}{10.2}<\frac{10.2x}{10.2x} \\ \\ 77 \end{gathered}[/tex]
Therefore, the spending will be more than $84 billion more than 7 years after 2003.
ANSWER:
7 years.
