Question

What is the relative maximum and minimum of the function?

f(x) = 2x2 + 28x - 8
A. Minimum Value: -106 Range y > -7
B. Minimum Value: -106 Range y > -106
C. Minimum Value: 7
Range y > 7
D. Minimum Value: -7 Range y > -7

Answer 1

Its not A but i think its D:)

Answer 2

@skullpatrol

Answer 3

find the vertex, use
\[\large x = \frac{ -b }{ 2a }\]

Answer 4

(0.28,0) ?

Answer 5

Or im not sure

Answer 6

One step at a time.
For\[\large f(x) = ax^2 + bx +c\]use\[\large x = \frac{ -b }{ 2a }\]

Answer 7

x= -28/2*2?

Answer 8

-7?

Answer 9

Correct. Now plug that into the equation, to get the minimum.

Answer 10

f(x)= 2(-7)^2+28(-7)-8 ?

Answer 11

yes

Answer 12

Okay well this is the part im bad at umm -7*-7 is 49 right?

Answer 13

Yes, just follow order of operations.

Answer 14

98....idk how to do this part +28(-7)-8

Answer 15

-106?

Answer 16

Just simplify one thing at a time

2(-7)^2+28(-7)-8

2*49 - 196 - 8

98 - 196 - 8

-106

Answer 17

Ok so my answer would be A right? I put A and i got it wrong

Answer 18

No, -7 has nothing to do with the range. The range is y > the minimum value, which is -106

Answer 19

Oh so it's B ?

Answer 20

Yes

Answer 21

Thanks so much ! :)

Answer 22

You're welcome! But, you said you got it wrong already??!

Answer 23

Yeah, but im correcting my test to retake it and get a better grade /.\

Answer 24

Oh okay