Coordinate Geometry Flashcards Preview

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Flashcards in Coordinate Geometry Deck (25):
1

What does "gradient" or "slope" describe in normal English words?

It describes how steep or slanty a line is.

2

What is a "coordinate" or "coordinate pair"?

It's two numbers inside brackets that tell you where a point is.

(x, y)

The first value tells you how far left/right it is from the origin. The second value tells you how far up/down it is from the origin.

3

What does "y-coordinate" mean?

It's the second value in a coordinate (x,y).

4

What does "x-coordinate" mean?

It's the first value in a coordinate (x,y).

5

How can we use the gradient to see that two lines are perpendicular? 

The gradients of perpendicular lines are the negative reciprocal. For example, 

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6

What does a table of values tell you?

It tells you a bunch of example coordinates that are on the line you want to draw. 

7

What is a quadrant?

A quarter of the graph.

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8

What does "x-intercept" mean?

Where the line crosses the x-axis.

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9

What does y-intercept mean?

Where the line crosses the y-axis.

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10

What is an independent variable?

It's the variable that influences another.

 

For example, the grade you get on a test depends on how much you study. Therefore, the amount you study is an independent variable.

11

What is a dependent variable?

It's the variable that depends on the other.

For example, the grade you get on a test depends on how much you study. Therefore, your grade is a dependent variable.

12

On which axis do we put the independent variable?

The horizontal axis. (The x-axis.)

13

What does "linear" mean when graphing?

It makes a straight line.

14

What does an equation of a line do? For example, y=x+3?

It tells you about the relationship of x and y. There are infinite x and y points that make a line. This means that for any x you choose, you can use the equation to find what the y must be in order for the point to be on the line.

15

What is "gradient-intercept" or "slope-intercept" form?

y=mx+c

16

In the equation y=mx+c, which letter represents the y-intercept?

(Be careful to notice the sign in front of c. This is also part of the y-intercept.)

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17

In the equation y=mx+c, which letter represents the gradient?

(Be very careful not to include "x". This is only the number BEFORE the x. There is no x in the gradient; it's just a number.)

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18

What are the two methods to graph the equation Ax+By=C?

  1. Use algebra to rearrange the formula into gradient-intercept form (y=mx+c).
  2. Find the intercepts and connect the dots.

19

What is the gradient of a vertical line?

The gradient of a vertical line is undefined.

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20

What is the gradient of a flat horizontal line?

0

 

(Because we go zero steps up, and 0 ÷ anything=0.)

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21

How can we use the gradient to see that two lines are parallel?

Parallel lines have the same gradient.

22

How do you know if a given point lies on a given line?

Plug in the x and y values from the point into the equation and see if it works.

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23

How do you calculate the gradient?

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24

How do you graph a line of the form y=mx+c?

  1. Mark the y-intercept (which is c  from the equation) on the y-axis.
  2. Use the gradient (which is m from the equation) to count over to the next point.
    • Count up/down
    • Count over to the right 

25

How do you find the equation of a line by looking at the graph?

  1. Look at the graph to find the y-intercept.
  2. Find a second point that goes through a perfect coordinate.
  3. Find the slope by count how far up/down and how far right you go from the left point to the right point.
  4. Write y=mx+c, where m is the slope and c is the y-intercept.