A
y = 2x + 5
Work out the value of y when x = 3.
Write the coordinate.
(3, 11)
Write the y-intercept and the gradient
y = 2x - 4
y-intercept (0, -4)
gradient 2
How to find the gradient of a line?
calculate change in y / change in x
What the variable represents y-intercept?
Work out y = 2x - 3 when x = -3
y = -9
The equation of straight-line graph
y=mx+c
Does the point (1, 9) lie on the line y = 2x + 5?
Explain.
No. When x = 1, y = 2.
1 + 5 = 7 not 9.
The point does not lie on the line.
The line goes through the origin.
What does it mean?
The origin is through the point (0, 0)
The line goes downhill (\)
so the gradient is... .
Negative
Work out the y-intercept for y = -3x - 4
(0, -4)
The line goes uphill (/)
so the gradient is... .
Positive
What the variable represents gradient?
m
Write an equation in straight-line form
for gradient -4 and y-intercept (0, 5)
y = -4x + 5
Does the point (2, 5) lie on the line y = x + 5?
No
The equation of a line is 3y - 8x = 12.
Work out x when y = 0
x = -3/2 = -1.5
What vehicle do I use to work?
Feet and Legs
When Miguel was 6 years old, his little sister, Leila, was half his age. If Miguel is 40 years old today, how old is Leila?
She is 37 years old
Which of these points lie on the line y = x + 5?
A. (0, 5)
B. (1, 7)
C. (2, 8)
D. (3, 9)
E. (4, 9)
Write in common form
m = 1/2
c = -4/5
y= 1/2x - 4/5
A line has gradient 4 and intersect the y-axis at (0, -3).
Write the equation of the line.
y = 4x - 3
Which of these are equations of straight lines?
A. y = 2x + 5
B. y = x2
C. y = 2/x
D. y = -1/2 x + 4
E. y = 3x2 + 7
A and D
What is the full name of Ms Suzie ?
Suzannah Katy Lowe (first and last only needed)
What is the closest country to Ms Suzie's original home.
Wales
In two years, Tom will be twice as old as he was five years ago. How old is Tom?
12 yo
You know 2 + 2 gives you the same total as 2 x 2. Find a set of three different whole numbers whose sum is equal to their total when multiplied.
The three different whole numbers whose sum is equal to their total when multiplied are 1, 2, and 3.