14 - Straight Line Graphs Flashcards
How would you represent x > 2 and x ≥ 2 on a graph
Draw a line along x = 2 and shade the right
for x > 2 make it dotted
for x ≥ make it full
How do the gradients compare between two parallel lines?
They are equal
How do the gradients compare between two parallel lines?
They are negative reciprocals
e.g. 2x -> -1/2x
How would you draw a line on a graph without plotting lots of points?
Using the x=0 y=0 method where you substitute x as 0 to find y at that point and vice versa. then join up the points.
How do you find the root of an equation?
Solve for x
How do you find the y - intercept of an equation?
the c value
How do you find the turning point of an equation?
complete the square of the equation. Your co-ordiantes will be ( -1b , c )
How do you know if an equation has a minimum or maximum turning point?
Positive coefficient mean it has a minimum TP
Negative coefficient means it has a maximum TP
How do you work out the discriminant and what can it tell you?
(b² - 4ac)
D > 0 2 roots
D = 0 1 root
D < 0 No roots
What does the area under a velocity time graph tell you?
The distance travelled
How do you work out the acceleration at a point of a V/T graph if it is curved?
Draw a tangent that meets the curve at that point and work out the gradient of the tangent