Graphs

Question 1

What is the equation of a straight line

Answer 1

Y= mx+c

Question 2

How do you calculate the gradient

Answer 2

Change in y ÷ change in x

Take two different points on the same line.

Question 3

How do you calculate the y intercept (c)

Answer 3

Rearrange y = mx+c

Y-mx =c

Question 4

What is the gradient of a perpendicular line

Answer 4

-1/m

Question 5

How do you calculate frequency density

Answer 5

Frequency density = frequency ÷ class width

Question 6

What shape is a quadratic graph and what value of x forms it

Answer 6

x^2

It makes a U shape

It makes an N shape if its a negative quadratic graph

Question 7

What shape is a straight line graph and what value of x forms it

Answer 7

X
It is a straight line

Question 8

What shape is a cubic graph and what value of x forms it

Answer 8

X^3

It looks like an elongated ‘s’ and has two turning points

           /
          /    \_\_\_\_\_/   /  / /

Or

/    /   /  / /

Question 9

What shape is a reciprocal graph and what value of x forms it

Answer 9

1/x

It will never touch the axis

Question 10

When translating a graph what do you do when:

af(x)

Answer 10

Multiply Y coords by a

Question 11

When translating a graph what do you do when:

F(x) + a

Answer 11

Add a to the y coords

Question 12

When translating a graph what do you do when:

-f(x)

Answer 12

Multiply the y coords by -1

(Reflect in the x axis)

Question 13

When translating a graph what do you do when

f(ax)

Answer 13

Divide x coord by a

Question 14

When translating a graph what do you do when

F(x+a)

Answer 14

Subtract a from the x coords

Question 15

When translating a graph what do you do when

F(-x)

Answer 15

Divide x by -1

(Reflect in the y axis)

Question 16

What do you do when ‘a’ is inside the brackets

Answer 16

It applies to x
And it does the opposite of what you would expect (appart from -x)

Question 17

What do you do when ‘a’ is outside the brackets

Answer 17

Effects the y values
Does what you expect