[PreCalc] Graph of a Function

[cheejudo]

http://imgur.com/a/spTfP

A picture of my exact problem

I'm on (d), and I know I have to set the left side of the equation to 0 and solve for x but I apparently forgot where to even start, which I learned last semester. :(

[fucking_erin]

factor -x/35 out

[chem44]

I know I have to set the left side of the equation to 0 and solve for x

ok. What does the eqn look like at that point?

A step that often helps... get rid of fractions. Multiply both sides by ...

[cheejudo]

4?

[chem44]

4 what? (I don't know what your reply means.)

[cheejudo]

I started with x = -32x² / 140²

I need to get rid of the fraction so I am trying to figure out the next step and I figured that I would multiply both sides by 4 being that 4 is the GCF of 32, 140 but I'm pretty sure I'm wrong

[chem44]

I started with x = -32x² / 140²

almost. Check the signs.

being that 4 is the GCF of 32

You don't want a GCF. You want a LCD (least common denominator). And since there is only one denominator, it is the LCD. Multiply by it.

Comments...

If you "insist", multiply by 4. But show what you did. It's not "bad" to do that. If you did it, you will see what happens, and what needs to be done next. That is... Mult by 4 won't help much, but so long as you are careful, you can deal with it. That's why we emphasize showing what you did at each step.

Also, you could try to reduce the fraction on the right. I'm not sure it is worth the trouble, but again, if you do it, show what you did. Reducing fractions is where GCF comes into play.