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Mathematics => Algebra => Topic started by: Jared on March 29, 2011, 11:24:15 pm

Title: Y-Intercept and Slope Help
Post by: Jared on March 29, 2011, 11:24:15 pm

I have the following problems for my Algebra Course:

• 3x+4y=8
• 10x-5y=10
• 6x+2y=20

I've got like 7 of these, but I can't get the answers right.. Just wondering HOW you do them? Just do the first one I would like to figure these out, but just get me started?

Please?

Title: Re: Y-Intercept and Slope Help
Post by: Webmaster on April 01, 2011, 04:55:42 pm

We would be happy to get you started!

First;
You know that there is a y=mx+b form, therefore all you have to do is just get those equations in that form in order to get your slope and y-intercepts! :)

Take the first one for example: 3x+4y=8 All you have to do is this,

1. Subtract 3x from BOTH sides! = 4y=8-3x
2. Divide by 4 to get Y by itself to BOTH SIDES! = y=2-3/4x
3. Use the y=mx+b form to get your answers!

Therefore, your y-intercept is the one without the x so it is 2 and the slope is equal to -3/4! Hope this helps!

Title: Re: Y-Intercept and Slope Help
Post by: Jared on April 08, 2011, 11:40:35 am

I got them a while back, and it did help however, I am confused.. why can't you add 3x and 8 to equal 5x?

Kind of confusing to me.. :(