Graphing Linear Equations

Question 1

What to do if you have equation and want to find x and y intercept?

3x-2y=6

Answer 1

Set x or y to 0 and calculate

Question 2

What is change in x y in slope 2/3

Answer 2

change Y / change X

Question 3

Slope Formula?

Answer 3

m= Y2-Y1 / X2-X1

Question 4

What is the slope of a vertical line?

And of a horizontal one?

Answer 4

it is called undefined, because you divide with 0 which isn´t possible?

Vertical is always 0 because numerator is 0 so result is always 0 too.

Question 5

2x+y=4. what is the slope?

Answer 5

-2x
y=-2x+4
m=-2

Always convert to slope intercept formula first

Question 6

-y=-3x+5. In these cases, how to get away the negative sign?

Answer 6

Divide every number(not only each on one side, all numbers on all sides) by -1 so you can change the signs(from neg to pos and pos to neg)

y=3x-5

Question 7

3x-y=5
3x-y=9
Are these lines parallel?

Answer 7

yes. Always calculate the slope. If same, they are parallel. You can get the lines into slope intercept form just to easy see if slope is the same.

Question 8

How to find out if 2 lines are perpendicular? (Have a 90 degree crosspoint). Give an example!

Answer 8

look at the slope. They need to have different signs and flipped fraction positions.

1/6
-6

Question 9

How can one graph a linear inequality?

How to calculate it?

y<1/2x-3

Answer 9

put the formula in system. The space above or underneath the graph represents the y>