Chapter 6 - Geometry Strategies Flashcards
List the relationships of a square, circle, 30-60-90, 45-45-90 and equilateral triangle.
Square- If you know either side length, diagonal length, perimeter and area, you can calculate the rest.
Circle - If you know either radius, diameter, circumference, and area, you can calculate the rest
30-60-90, 45-45-90 and equilateral triangle - If you know either one side length and its corresponding angle, perimeter, and area, you can calculate the rest.
** For DS ques, remember all that’s imp is that you can ans the ques but you dont have to solve for it.
What are the principles of Geometry?
Two imp principles of Geometry are:
1) Dont assume what you dont know for sure. Ex: two lines are drawn to look parallel and intersected by a third line perpendicuar. Unless, you are told that the two lines are parallel, dont assume anything. Therefore, you are unable to ans the question.
2) Use every piece of info you do have to make further inferences. Ex: if you are told that two parallel lines are intersected by a third line. Now you have enough info to ans the quest bc when parallel lines are intersected by a third line, the eight angles created by a third line are all related. Therefore without knowing the exact value of x + y or x or y, you can ans the ques bc a straight line has a degree of 180 and the angles x y together make up 180. Therefore, x+y=180
What are some shapes in shapes and their bridge?
1) Circle inscribed in a square = Bridge= Side of square = diameter of the circle.
2) Triangle in rectangle = bridge= Length + width of rectangle= base + height of triangle.
3) Triangle in Trapezoid = Bridge = Height of trapezoid = height of triangle
4) Triangle in Circle = Bridge = Radius of circle = sides of triangle.
5) Square in Circle = Bridge = Diameter of circle = Diagonal of square
