Formulae Flashcards
basic weekly wage
basic wage * hours worked
overtime wage
basic wage * 1.5 (time and a half or double time) * hours worked
Calculating cost price given profit%
(SP)$/(SP profit)%* 100= CP
Calculating cost price given loss%
(SP)$/(SP loss)% * 100= CP
finding % profit
P/CP*100
finding % loss
L/CP*100
Calculating selling price given profit %
percent added to 100/100 * CP
Calculating selling price given loss %
percent subtracted from 100/100 * CP
simple interest
SI= P * R * T/100
Principal
P= SI * 100/R * T
Rate
R= SI * 100/P * T
Time
T= SI * 100/P * R
Final Amount for Simple Interest
P+ SI
Compound Interest
Amount accruing(A)= P (1+r/100)^n
Final amount for Compound Interest
Amount accruing - Principal
equation of a line
y=mx+c
length of a line
(x2 - x1)^2 + (y2 - y1)^2 square rooted
m/gradient
y2 - y1 / x2 - x1
mid point/M
(x2 + x1 /2), (y2 + y1 /2 )
completing the square
h= b/2a
completing the square
k= 4ac-b^2/4a
quadratic expressions where h and k are constant
a (x+h)^2 +k
When to use SINE rule
Two angles, one side
OR
two sides, and a non-included angle
When to use COS rule
Three sides
OR
Two sides and the included angle.
Pythagoras Therom
c² = a² + b²
c² being the hypotenuse
a² = c² - b²
b²= c² - a²
SQUARE ROOT AFTER
When are phythagoras therom and the trigonometric ratios used?
RIGHT ANGLED TRIANGLES ONLY
BEARINGS
- Try and draw it
- Always have 3 digits
- Start from NORTH, THEN MOVE
- Alternate angles (form a z) and corresponding angles (parallel) r equal
- Straight line and interior angles are equal to zero
- Bearings move in a CLOCKWISE DIRECTION ONLY
- horizontal plane simply means flat surface CHILL 😎
ANGLE or point or vertices
CAPITAL LETTERS
Length of a side or side or length
common letters
If x = to a constant/a whole number the line is…
Vertical and parallel to the x-axis
If y is equal to a whole number or constant it is…
Horizontal and parallel to the x-axis
(x, y)
(-h, k)
If the line is the perpendicular bisector…
The gradient is the negative reciprocal