Quant 3 LInear And Quadratic Equations Flashcards
(9 cards)
1
Q
Three common quadratic identities: (x+y) ²
A
(x+y) ² = x² + y ² + 2xy
2
Q
Three common quadratic identities: (x-y) ²
A
(x-y) ² = x ² + y ² - 2xy
3
Q
Three common quadratic identities: (x+y)(x-y)
A
(x+y) (x-y) = x ² - y ²
4
Q
How can we find g: 7s + 5g = 70, s>0
A
7s + 5g = 70, s>0
Mult of 7 + Mult of 7 = Mult of 7
-> 5g must be mult of 7
=> g must be mult of 7: 7, 14, 21
-> if g=14, s must be 0, since it‘s not, g=7
5
Q
x ² + y ² + 2xy
This expression can be written as
A
(x+y) (x+y)
6
Q
x ² + y ² - 2xy
This expression can be written as
A
(x-y) (x-y)
7
Q
x ² - y ²
This expression can be written as…
A
(x+y) (x-y)
8
Q
What is the difference of two squares?
A
(x+y) (x-y) = x ² - y ²
9
Q
x-y/y-x=
A
-1
