Important Facts on Area of Triangle and Ratio

Area of Triangle

1. Factors involved - base and height; where height is a perpendicular line at right-angle with the base and joining the base and the vertex (pointed tip) opposite the base.

2. Counting square units method and Cut-and-paste method

3. Formula - ½ x base x height

4. How to find a shaded part in a figure? - first, you have to find the total area of the figure (either triangle, square or rectangle). Then find the unshaded part (which can be 1 part or several parts). The last step would be taking the total area minus the area of the unshaded part.

5. How to find an unshaded part in a figure? - first, you have to find the total area of the figure (either triangle, square or rectangle). Then find the shaded part (which can be 1 part or several parts). The last step would be taking the total area minus the area of the shaded part.


Ratio

My 6 important points for ratio are:
1. No units - remember, only numbers are represented.
2. Show all your working - by working, I meant for you to show what number you divided or multiplied to get your answer.
3. Labels - make sure you write these at the beginning of every word problem so it helps you to see clearer and better.
4. Proportion - whatever you multiply with or divide by on one side of the ratio, you have to do exactly the same for the other side of the ratio too (meaning they always increase or decrease by the same amount).
5. Underline or highlight keywords (so you'll know which item/quantity comes first, which one comes second and so on).
6. Reducing to simplest form - make sure you know your equivalent ratios well. Reduce all your answers to the simplest forms for every question unless it states otherwise.