Question

Identify the vertex for the graph of y = 2x^2 + 8x − 3

Answer 1

x = -b/2a = -8/2(2) = -8/4 = -2

2(-2)^2 + 8(-2) - 3 = 8 - 16 - 3 = 8 - 19 = -11

(2,-11)

Answer 2

(-2,-11)

Answer 3

Mandolino

Answer 4

the form y=a(x-h)^2+k has vertex (h,k) and can be found by completing the square\[y=2(x^2+4x+4)-3-8\]\[y=2(x+2)^2-11\]vertex is (-2, -11)

Answer 5

Why on earth would you do all of that work?

Answer 6

i didn't know i was in a race with hero; i thought you left

Answer 7

also, i find the other way tedious

Answer 8

In what way?

Answer 9

It's by far the easiest way

Answer 10

all that squaring and multiplying and adding and subtracting... it way too much like maths

Answer 11

Oh, I get it. It's not "systematic" or "algebraic". Kind of reminds me of why I hate the quad formula

Answer 12

here we go again...

Answer 13

And your way is better in what way? You do the same things...

Answer 14

just a preference; we better be careful we may get called the orifice of a digestive system again

Answer 15

the end, not the beginning of the system

Answer 16

WTH Mandolino

Answer 17

don't you remember that guy yesterday when i wrote kids these days

Answer 18

I don't remember being called anything. I must have overlooked that part

Answer 19

Determine whether the graph of y = 4x2 + 5x − 8 opens up or down and whether it has a maximum or minimum point.

Up; Minimum

Up; Maximum

Down; Minimum

Down; Maximum

Answer 20

when the lead coefficient, 4 in this problem, is positive the parabola opens upward and thus the vertex is a minimum

Answer 21

Identify the solutions of 3x^2 + 14x + 8 = 0.

Answer 22

(3x+2)(x+4)=0
x=-2/3 or x=-4

Answer 23

Solve x^2 − 7x + 12 = 0

Answer 24

(x-4)(x-3)=0
x=4 or x=3

Answer 25

That's not systematic Mandolino

Answer 26

What are the x-intercept(s) of the graph of y + 30 = x^2 + x?

(−5, 0) and (6, 0)

(−5, 0) and (−6, 0)

(5, 0) and (−6, 0)

(5, 0) and (6, 0)

Answer 27

Safari King must be one of those online testers

Answer 28

y=x^2+x-30=(x+6)(x-5)=0
x=-6 or x=5

Answer 29

Nope

Answer 30

a lot of HW

Answer 31

Just a person in need of MAJOR MATH HELP

Answer 32

Where does the graph of y = 3x^2 − 10x − 8 cross the x-axis?

Answer 33

any others, I've got about 7 minutes

Answer 34

What is true about the solutions of a quadratic equation when the radicand of the quadratic formula is a positive number that is not a perfect square?

No real solutions

Two identical rational solutions

Two different rational solutions

Two irrational solutions

Answer 35

What are the exact solutions of x^2 − 5x − 7 = 0?

Answer 36

y=3x^2-10x-8=(x-4)(3x+2)=0
x=4 or x=-2/3
the points are (4,0); (-2/3,0)

Answer 37

What is true about the solutions of a quadratic equation when the radicand of the quadratic formula is a positive number that is not a perfect square?
answer = two irrational solutions

Answer 38

What are the approximate solutions of 2x^2 + x = 14 rounded to the nearest hundredth?

x ≈ −2.41 and x ≈ 2.91

x ≈ −2.91 and x ≈ 2.41

x ≈ −5.82 and x ≈ 4.82

No real solutions

Answer 39

you have to use quadratic formula to solve

What are the exact solutions of x^2 − 5x − 7 = 0?

Answer 40

Just keep that question of exact solutions

Answer 41

skip*

Answer 42

discriminat=25-4(-7)=53 then\[x=\frac{5 \pm \sqrt{53}}{2}\]

Answer 43

Solve 3x2 + 5x + 7 = 0. Round solutions to the nearest hundredth.

No real solutions

x ≈ −6.34 and x ≈ 1.34

x ≈ −0.45 and x ≈ 2.11

x ≈ −2.11 and x ≈ 0.45

Answer 44

What are the approximate solutions of 2x2 + x = 14 rounded to the nearest hundredth?

x ≈ −2.41 and x ≈ 2.91

x ≈ −2.91 and x ≈ 2.41

x ≈ −5.82 and x ≈ 4.82

No real solutions

Answer 45

What are the approximate solutions of 2x^2 + x = 14 rounded to the nearest hundredth?
2x^2+x-14=0
D=1-4(2)(-14)=113 so\[x=\frac{-1 \pm \sqrt{113}}{4}\]

Answer is
x ≈ −2.91 and x ≈ 2.41

Answer 46

Solve 3x2 + 5x + 7 = 0. Round solutions to the nearest hundredth.
D=25-4(2)(7)<0
so the answer is
No real solutions

Answer 47

A firecracker shoots up from a hill 145 feet high with an initial speed of 80 feet per second. Using the formula H(t) = −16t2 + vt + s, approximately how long will it take the firecracker to hit the ground?

Answer 48

i think i got them all

Answer 49

Darlene kicks a soccer ball off the ground and in the air with an initial velocity of 34 feet per second. Using the formula H(t) = −16t2 + vt + s, what is the maximum height the soccer ball reaches?

Answer 50

Are you going to make us take the whole test?

Answer 51

i think you will have to repost; i only had until the top of the hour; sorry

Answer 52

Using graphing technology, approximate the solutions of 0.35x2 − 2.52x + 1.34 = 0.

x ≈ 0.12 and x ≈ 4.56

x ≈ 0.58 and x ≈ 6.62

x ≈ 1.17 and x ≈ 6.14

x ≈ 1.83 and x ≈ 4.84

Answer 53

its just HW i'm pretty sure

Answer 54

Oh okay. Well Thanks Anyways You were a HUGE help

Answer 55

later SK and Hero

Answer 56

Mandolino, you're too nice and too assuming

Answer 57

:})

Answer 58

Yeah he's something you need to be hero

Answer 59

:P

Answer 60

gn

Answer 61

I'm already a hero

Answer 62

In fact, I'm a master :P

Answer 63

and a master