Question

Write the correct description of the graph of the inequality -4x<20.
Can someone PLEASE show me how to do this, i have to take a test that is going to have a bunch of similar questions like this one.

Answer 1

first simplif:y

-4x < 20

divide both sides by -4:
x > -5

note: dividing by a negative quantity reverses the inequality sign

Answer 2

can you continue ?

Answer 3

mmm no sorry, do i divide 1 from both sides?

Answer 4

no, now we can draw the graph;
the graph is a straight line with an open circle at -5 and shaded on the right

(its an open circle because the result does not include -5)

Answer 5

oh ok thank you, so all i have to do is simplify and write out the answer?

Answer 6

Quick lesson :
you solve it just like an equation except for the rule. when dividing/multiplying by a negative, the inequality sign changes.
if there is an equal sign involved, it will be a closed circle.
if no equal sign, it will be an open circle.
if it is less then, shading goes to the left.
if it is greater then, shading goes to the right

Answer 7

Thank you both, i understand

Answer 8

yw

Answer 9

glad we could help :)