5(4/5)^2+8(4/5)-6 =???

- Denise

5(4/5)^2+8(4/5)-6 =???

- Stacey Warren - Expert brainly.com

Hey! We 've verified this expert answer for you, click below to unlock the details :)

- chestercat

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

- anonymous

18/5

- Denise

how did you get that

- anonymous

see 5 (4/5)^2 is 5 (16/25) = 16/5

Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

- anonymous

8(4/5) = 32/5

- anonymous

u add both f these u get 48/5

- anonymous

then u subtract 6
which is
(48/5) - 6
(48-30)/5
18/5

- anonymous

got it?

- Denise

thanks! I am trying to do relative minima and maxima
problems

- Denise

I am lost as hell!

- anonymous

how old r u?

- Denise

40

- Denise

just went back to college

- anonymous

kk

- anonymous

ur my mums age almost

- Denise

haha

- anonymous

cn i help smwher?

- Denise

that would be awesome

- Denise

how do you determine when it is a minima or a maxima

- anonymous

see lets take an example of a cubic function f(x)

- anonymous

when you differentiate it to get f'(x) , u evaluate the roots of f'(x)

- anonymous

these r called critical points...these are the points where it can be maximum or minimum..the function that is

- anonymous

get it til here?

- Denise

k.

- Denise

got that

- anonymous

so now to determine whether its max or min, what u do is u differentiate once more to get f''(x)..now plug in ur critical point into it

- Denise

Are you going to be on here long today? I have about 60 problems I have to do.

- Denise

What determines if it is maxima or minima?

- anonymous

when u plug the point into f''(x), see the sign of the function

- Denise

if its negative its min and positive max?

- anonymous

if the sign of f"(x) is negative its maxima, and viceversa

- anonymous

no the opposite

- Denise

gotcha!
Thanks a million!

- anonymous

m not gonna b long inuf fr 60 problems..bt as much as i can

- Denise

thanks
I am afraid I will be on here all weekend

- anonymous

no prob...well see wt we cn crack

- Denise

According to th answer on mymathlab, the answer was -46/5.... how is that

- amistre64

nuthin wrong with 40s :)

- anonymous

well amistre check on that question she posted

- amistre64

which one?

- anonymous

right on top..

- Denise

I really appreciate yall helping me!!!1

- amistre64

5(4/5)^2+8(4/5)-6 =??? this one

- Denise

yep

- anonymous

yeah

- amistre64

5x^2 +8x -6 is a parabola; that looks like a bowl sitting on the counter; it has a local minimum at its vertex; ....i sctually finished typing this reply like 40 seconds ago; slow response time i guess

- amistre64

-b/2a = x compnent; -8/2(5) = -4/5 right?

- amistre64

5(-4/5)^2+8(-4/5)-6 = y
^^^
use (-)4/5

- amistre64

5(16/25) +8(-4/5)-6 = y

- anonymous

yeah denise i thought it was 4/5 while actually its -4/5

- amistre64

16 -32 -6
--------- =
5 5 1

- amistre64

6(5) = 30 s000
(16-32-30)/5

- amistre64

-46/5

- amistre64

makes sense?

- anonymous

yeah

- Denise

k

- Denise

where did the 6(5) come from???

- anonymous

cz u take the lcm while subtracting

- Denise

to get the 30

- amistre64

yeah; fractions reguire you to be wearing the same pants; and that 6/1 is not dressup for company; so we got to changes its clothes to match .... we put it in 5 pants and find a top to match

- Denise

lol!

Looking for something else?

Not the answer you are looking for? Search for more explanations.