Things i dont understand before an exam Flashcards
1
Q
How do you work out compound interest?
A
original x (multiplier)*to the power of how many years
2
Q
How do you work out simple interest?
A
original + n(original x decimal percentage)
3
Q
How to work out percentage change?
A
change/original x 100
4
Q
How to find the original amount after a percentage increase
A
amount/multiplier
5
Q
When completing the square what does
x[2] + 2bx+c equal?
A
(x + b)[2] - b[2] + c
6
Q
When completing the square what does
x[2] - 2bx+c equal
A
(x - b)[2] - b[2] + c
7
Q
if you square root one side of the equation, the other side is both + or - e.g
(x+3)[2] = 9 is re arranged to x + 3 =
A
9 or -9
