Question

Compare and contrast the two quadratic equations below. In order to receive full credit, use complete sentences to describe the following:

The direction each parabola opens
The vertex of each parabola
y = x^2 − 2x
y = −2x^2 + 4x − 3

Answer 1

You can tell which way the parabola opens up by looking at the sign of it's first term. The first one opens up (because the x is positive) and the second one opens down (its x is negative). To find the vertex of each parabola use this formula: vertex=-b/2a,-b^2-4ac/4a

Answer 2

thank you!! lol i didnt get this at all but i kinda do now

Answer 3

Think of your equation having specific parts.

y=−2x^2 + 4x − 3

The general form of this equation would be:
y=ax^2+bx-c

Each letter stands for a term. To find the vertex of this parabola, we just use the formula:
-4/2(-2),-4^2-4(-2)(-3)/4(-2)
-4/-4,16-24/-8
1,-8/-8
Vertex= 1,1

Answer 4

vertex=-b/2a,-b^2-4ac/4a so a =-2 b=4 c=-3 and i just fill in that equation.

Answer 5

Yup. For the first parabola you don't have a C so you just fill in zero for C when you plug it into the formula.

Answer 6

is the / in the formula divide
??

Answer 7

Yes.

Answer 8

\[Vertex= \frac{ -b }{ 2a },\frac{ -b^2-4ac }{ 2a }\]

Answer 9

^4a

Answer 10

ok now im confused is that 2 ways to find it or one big formula that u multiply to each othere??

Answer 11

It's the same formula. You use it to find the vertex of ONE parabola.

Answer 12

You find one first and then the other.

Answer 13

for the first one i got 1

Answer 14

so i got 1 in the first part and -3/2 for the second do i multiply them