# Solving Exponential Equations

• Apr 22nd 2009, 06:17 PM
asimon2008
Solving Exponential Equations
Hello I'm a newbie. I need help with my homework. I have ADD bad. I don't understand this section Could someone please show how to work these problems?

In Ex. 9-16 solve the equation f(x)= g(x) algebraically.

11. f(x)=5^x-2-15
g(x)=10

In Ex 43-60 solve the exponential equation algebraically. Round your result to three decimal places. Use a graphing utility to verify your answer.

43. 8^3x=360

45. 2e^5x=18

47. 500e^-x=300
• Apr 23rd 2009, 01:29 AM
earboth
Quote:

Originally Posted by asimon2008
Hello I'm a newbie. I need help with my homework. I have ADD bad. I don't understand this section Could someone please show how to work these problems?

In Ex. 9-16 solve the equation f(x)= g(x) algebraically.

11. f(x)=5^x-2-15
g(x)=10

In Ex 43-60 solve the exponential equation algebraically. Round your result to three decimal places. Use a graphing utility to verify your answer.

43. 8^3x=360

45. 2e^5x=18

47. 500e^-x=300

First: Do us (and yourself!) a favour and use brackets! Otherwise your equations are not understandable.

Example: f(x)=5^x-2-15 and g(x)=10 should read f(x)=5^(x-2)-15 and g(x)=10

Second: I'll do #11 and leave the rest for you. If you need some further assistance show your work so we know where we could help you.

\$\displaystyle f(x)=g(x)~\implies~5^{x-2}-15=10~\implies~5^{x-2} = 25 = 5^2~\implies~\$ \$\displaystyle x-2 = 2~\implies~x=4\$
• Apr 23rd 2009, 01:33 AM
pickslides
Quote:

Originally Posted by asimon2008
Hello I'm a newbie. I need help with my homework. I have ADD bad. I don't understand this section Could someone please show how to work these problems?

In Ex. 9-16 solve the equation f(x)= g(x) algebraically.

11. f(x)=5^x-2-15
g(x)=10

In Ex 43-60 solve the exponential equation algebraically. Round your result to three decimal places. Use a graphing utility to verify your answer.

43. 8^3x=360

45. 2e^5x=18

47. 500e^-x=300

You probably have to be a bit clearer with your questions my friend

For example is your question 11 supposed to be

\$\displaystyle f(x)=5^x-2-15\$

\$\displaystyle g(x) =10\$

or

\$\displaystyle f(x)=5^{x-2}-15\$

\$\displaystyle g(x) =10\$