# EIV Flashcards

1
Q

Whether 2 equations involving 2 variables will be sufficient to solve for the variables

A

If both equations are linear - that is if there are no squared terms and no (xy) terms - the equations will be sufficient unless the two equations are mathematically identical

2
Q

Whether 2 equations involving 2 variables will be sufficient to solve for the variables

A

If there are any non-linear terms in either of the equations (x^2, xy, or x/y), there will usually be two (or more) different solutions for each of the variables and the equations will not be sufficient

3
Q

x² - y² =

A

(x+y) (x-y)

4
Q

x² + 2xy + y² =

A

(x+y) (x+y)

5
Q

x² - 2xy +y² =

A

(x-y) (x-y) or (x-y)²

6
Q

a² - 1 =

A

(a+1) (a-1)

7
Q

Inequalities: When dividing or multiplying by a negative number…

A

…the inequality sign flips

8
Q

4 - 3x < 10 =

A

x > 2

9
Q

Inequalities: You should never…

A

…subtract or divide inequalities

10
Q

Inequalities: You can only…

A

multiply when you know both variables are positive

11
Q

3 x LT8 =

A

LT24

12
Q

8 + LT2 =

A

LT10

13
Q

8 - LT2 =

A

GT6

14
Q

6 x LT3 =

A

LT18

15
Q

-6 x LT3 =

A

GT-18

16
Q

8 / LT2* =

A

GT4 *If we know LT2 is positive

17
Q

Square roots: You cannot…

A

…square root a negative number