Problem - Solve Two Ways

TheJason

Staff member
Moderator
Isolate l.

$$\displaystyle \dfrac{8 + k}{m} = \dfrac{1}{l}$$

MarkFL

La Villa Strangiato
Staff member
Moderator
Math Helper
a) Invert both sides to obtain:

$$\displaystyle l=\frac{m}{k+8}$$

b) Cross multiply to obtain:

$$\displaystyle l(k+8)=m$$

Divide through by $$k+8$$:

$$\displaystyle l=\frac{m}{k+8}$$

harpazo

harpazo

Pure Mathematics
Banned
a) Invert both sides to obtain:

$$\displaystyle l=\frac{m}{k+8}$$

b) Cross multiply to obtain:

$$\displaystyle l(k+8)=m$$

Divide through by $$k+8$$:

$$\displaystyle l=\frac{m}{k+8}$$
You know all the tricks.

TheJason

Staff member
Moderator
Who are we kidding here? Of course, inverting is the easiest - but the other way isn't much harder.

harpazo

Pure Mathematics
Banned
Who are we kidding here? Of course, inverting is the easiest - but the other way isn't much harder.
Why do you talk to Mark this way? Are YOU kidding me???????

TheJason

Staff member
Moderator
Why do you talk to Mark this way? Are YOU kidding me???????
He should smack me!

MarkFL

La Villa Strangiato
Staff member
Moderator
Math Helper
I didn't feel there was anything bad or disrespectful about that post. Inverting was a one step process. It was very simple going that route.

TheJason

TheJason

Staff member
Moderator
There was no disrespect aimed at Mark. I was looking at the solution itself, apart from Mark suggesting it. Anyway, I knew the answers beforehand, but I posted the problem to see if other people knew.

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harpazo

Pure Mathematics
Banned
There was no disrespect aimed at Mark. I was looking at the solution itself, apart from Mark suggesting it. Anyway, I knew the answers beforehand, but I posted the problem to see if other people knew.
Your choice for words is the problem. Read your post again. I am talking about the words "of course." Example, if I walk into a dentist office and the doctor tells me that I have two cavities and I reply OF COURSE I KNOW WHAT A CAVITY IS, DOCTOR. This is a disrespectful reply.

It does not matter if I know what a cavity is. I do not know what a cavity is at the level of a dentist. You and I know basic math but Mark is a doctor of math compared to what we know about the subject. Understand? I'm sure you do not understand.