# How do you simplify and write (3.89)^-5 * (3.89)^6 with positive exponents?

Jun 15, 2018

See a solution process below:

#### Explanation:

Use this rule of exponents: ${x}^{\textcolor{red}{a}} \times {x}^{\textcolor{b l u e}{b}} = {x}^{\textcolor{red}{a} + \textcolor{b l u e}{b}}$

Substitute $3.89$ for $x$ giving:

${\left(3.89\right)}^{\textcolor{red}{- 5}} \times {\left(3.89\right)}^{\textcolor{b l u e}{6}} \implies {3.89}^{\textcolor{red}{- 5} + \textcolor{b l u e}{6}} \implies {3.89}^{1}$

If necessary, we can further simplify the expression using this rule of exponents:

${a}^{\textcolor{red}{1}} = a$

${3.89}^{\textcolor{red}{1}} = 3.89$