What are inequality? When do we use inequalities? What type of inequalities are there? Which symbols are used for each type?

Are the following expressions variable inequalities? Why?
a. 13z=27
b. x<0
c 3x+5x>11
d. y+5≤11
e. 7-1>- 32

B,C,D, and E

Step-by-step explanation:

Inequality tells us about the relative size of two values.

Mathematics is not always about "equals", sometimes we only know that something is greater or less than.

Example: Alex and Billy have a race, and Billy wins!

What do we know?

We don't know how fast they ran, but we do know that Billy was faster than Alex:

Billy was faster than Alex

We can write that down like this:

b > a

(Where "b" means how fast Billy was, ">" means "greater than", and "a" means how fast Alex was)

Inequalities: Symbols and Vocabulary

Algebra rules / General Rules:

 Isolate a positive x on the left side using algebra

 Reverse the inequality sign when mult/divide by a negative

 Less than: The symbol that:  Looks like an L () for ess than

< ○ )  Points to the Left



● ]  Caps the arrow pointing towards smaller numbers

on the number line

 Points towards the smaller of two numbers (4 < 7)

> Greater than: The symbol that: Looks like the top of an R ( >

)for GReater than

> ○ (  Points to the Right



● [  Caps the arrow pointing towards larger numbers on

the number line

 Open end is by the larger number (7 > 4)

Compound inequalities: usually in the form -4 < x < 4

but can also be x > -4 and x < 4

the answer is a.

135 and 80

step-by-step explanation: