Bob B.

asked • 09/06/16

How do you solve for x in this precalc equation?

5(72x)=4(35x)

1 Expert Answer

By:

Mark M. answered • 09/06/16

Tutor
5.0 (278)

Mathematics Teacher - NCLB Highly Qualified

See tutors like this
See tutors like this
5(72x) = 4(35x)
5/4 = (35x) / (72x)
1.25 = (35x) / (72x)
ln 1.25 = ln[(35x) / (72x)]
ln 1.25 = ln 35x - ln 72x
 
Can you solve it from here?
Upvote • 0 Downvote
More
Report

Bob B.

Sort of... I was looking for a log over a log.
Report

09/06/16

Mark M.

That can be achieved.
ln 1.25 = 5x ln 3 - 2x ln 7
ln 1.25 = x(5ln3 - 2ln7)
ln 1.25 / (5ln3 - 2ln7) = x
Report

09/06/16

Bob B.

Thanks, that was what I was looking for!
Report

09/06/16

Mark M.

Welcome!
Report

09/06/16

Still looking for help? Get the right answer, fast.

Ask a question for free

Get a free answer to a quick problem.
Most questions answered within 4 hours.

OR

Find an Online Tutor Now

Choose an expert and meet online. No packages or subscriptions, pay only for the time you need.