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Flashcards in Year 9 Yearlyz Deck (53)
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1

How do you factorise an algebraic expression

*Find the HCF of the terms and write it outside the brackets
*divide each term by the HCF and write the answers inside the brackets
* To check that it's correct expand it.

2

How to expand the difference of 2 squares

The rule is =
(a+b)(a-b) = a2 - b2

The answer is always a minus

3

What is commission

Commission is earned by sales people. It is calculated as a percentage of the value of items sold or income made.

4

How do you find the unknown angle

Shift tan 35 ab/c =

5

How to Find the surface area of a closed cylinder

2 x Pie x radius2 + 2 x pie x radius x height

6

How do we find the exterior angle of a triangle

It is equal to the sum of the two interior opposite angles
Triangle interior angle + triangle interior angle = triangle exterior angle

7

How do you find the net pay

Net pay= gross pay - tax - other deductions

8

How to expand a perfect square

(A + b)2 = a2 + 2ab + b2

E.g (m + 9)2
= m2 + 81m + 92

The 2 at the end are meant to be squared 2

9

What is continuous data

This can be any time of data such as 42.36263 degrees celcius

10

What is the sin

Opposite/hypotenuse

11

Look at the fat index laws in your photos

Ye

12

What is the median

The middle score

13

How to find the percentage profit

Profit/Cost Price X 100%

14

What is discrete data

Legit just whole numbers

15

Look at chapter 4 and learn

Yet

16

What is numerical data

Data that can be counted

17

Study CHAPTER 7

Do it

18

How to add or subtract algebraic fractions

To add or subtract factions, convert them (if needed) so that they have the same denominator, then simply add or subtract the numerators.

19

How to test for a Pythagorean triad

* square all numbers
* plus the first 2 numbers
* if it equals the third one it is a Pythagoras triad

20

What is categorical data

These can be put into categories such as someone's hair colour

21

What is the units of =
Kgs to grams
Hours to seconds
Kilometres to metres
Hours to minutes
Days to hours
Litres to mL

1kg = 1000 g
1h = 3600 s
1km = 1000m
1hr = 60 min
1d = 24 hrs
1L = 1000mL

22

How many minutes is 1 degree

1 degree = 60'

23

How to find the surface area

Find the area of each face and add the areas together
Make sure to square the answer at the end

24

How to factorise a quadratic trinomial E.g x2 + 6x + 8

E.g x2 + 6x + 8
=(x+__)(x+__)
=(x+2)(x+4)

This is because 2 + 4 is 6 and 2 x 4 is 8
You can find this by dividing 8 by 2,3,4 and then plusing the 2 to whatever you got or 3 to whatever you got.

25

How to find the area of a trapezium

Area= 1/2 x (side+side) x height

26

What is the mode

It is the score that occurs most

27

Power of a power? How to do

When raising a power to another power, multiply the powers together

28

Negative indices? How to do

A number raised to a negative power gives a fraction with a numerator of 1 then remove the - on the power

29

How do you multiply algebraic fractions

To multiply fractions, cancel any common fractions and then multiply the numerator and denominator separately e.g
=4/k x 3k/16
=3/4
This is because 4 16 4 times and k goes into k once

30

How do we write scientific notation

Numbers written in scientific notation are expressed in the form m x 10n

Where m is a number between 1 and 10 and n is an integer
YOU CAN ALSO DO IT ON THE CALCULATOR