Straight Lines

Question 0

Y = mx + c } equation of a straight line

Answer 0

M = gradient
C = y intercept

Question 1

/ is a

\ is a

Answer 1

Positive gradient

Negative gradient

Question 2

Gradient =

Answer 2

Rise/run

Question 3

How to sketch a straight line using y=mx + c

Answer 3

1) get the equation into the form ‘y = mx+c’
2) put a dot on the y axis at the value of c
3) then go along one unit and up or down by the value of m and make another dot
4) repeat the same ‘step’ in both directions
5) finally check that the gradient looks right

Question 4

How to find the equation of a straight line graph

Answer 4

1) from the axes identify the two variables (eg x and y)
2) find the values of m and c from the graph
3) using these values from the graph, write down the equation with the standard format y=mx+c

Question 5

Find the equation of a line with the gradient 2 which passes through the point (3,4)

Answer 5

Y=mx+c
Y=2x+c
4=2 x 3 + c
4 = 6 + c
C = -2
So the line equation is y = 2x -2

Question 6

Find the equation of the line joining the points (0,4) and (6,10)

Answer 6

1) Work out the gradient - rise/run - 6/6 - y distance over the x distance - G = 1
2) Substitute y=1x +c
3) doesn’t matter which coordinate is used (eg 0,4)
4) 4 = 1 x 0 + c
5) c = 4
6) y = x + 4

Question 7

Finding the midpoint of a line segment
A= (-2,4)
B= (8,10)

Answer 7

The coordinates of M are the average of the x coordinates and the average of the y coordinates.
Eg. (-2+8 /2 , 4+10 /2)
(3,7)

Question 8

Finding out the length of a line

Answer 8

Use Pythagoras’ theorem

Question 9

X = 1,2,3,4,5 etc
Y = 1,2,3,4,5 etc

Answer 9

X= vertical
Y= horizontal

Question 10

Y=x

X=y

Answer 10

Uphill

Downhill

Question 11

A in the equation of sloping lines y=ax/ y=-ax is the

Answer 11

Gradient and the bigger the a number, the steeper the slopes

Question 12

All straight line equations just contain

Answer 12

Something x, something y and a number

Question 13

A u shape quadratic graph is…

An n shape quadratic graph is…

Answer 13

X(sq)

-x(sq)

Question 14

Aim for a symmetrical bucket shape when you are

Answer 14

Plotting a quadratic graph

Question 15

Complete the table of values for the equation y=x(sq) + 2x - 3 and draw the graph

Answer 15

Use paper

Question 16

1/x graphs look like

Answer 16

2 folds from opposite quadrants

Question 17

X(cubed) graphs look like

Answer 17

A flat wiggle

Question 18

1/x(sq) graphs looks liike

Answer 18

Two lines from two quadrants next to each other meeting in the middle and moving upwards

Question 19

Parallel lines have the same value of m (gradient)

Answer 19

Substitute the other equation of the parallel line with the coordinates that are given to you for the parallel line you need the equation of