You can use grouping to isolate the variable in the equation \(mx+nx=p\)
\(mx+nx=p\) | Let's factor out an x from both sides terms on the left hand side of the equation. |
\(x(m+n)=p\) | Divide by m+n on both sides. |
\(x=\frac{p}{m+n}\) | |
The original expression is \(3^{-8}*3^5\). In order to do this, we can use the fact that the base of both exponents are the same and then simplify.
\(3^{-8}*3^5\) | Since the bases are identical, just add the exponents together. In general, \(a^b*a^c=a^{b+c}\) |
\(3^{-8}*3^5=3^{-8+5}=3^{-3}\) | A number to a negative exponent is the same as the inverse of a number to the same positive exponent. \(a^{-b}=\frac{1}{a^b}\) |
\(3^{-3}=\frac{1}{3^3}=\frac{1}{3*3*3}=\frac{1}{27}\) | This is your answer. |