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Equation of a circle with centre (0,0). Date: ______________. The equation of a circle with centre (0,0) and radius r is x 2 + y 2 = r 2. Example 1: What is the equation of the circle with the centre (0,0) and a radius of 9?. x 2 + y 2 = 81.
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Equation of a circle with centre (0,0) Date: ______________
The equation of a circle with centre (0,0) and radius r is x2 + y2 = r2. Example 1: What is the equation of the circle with the centre (0,0) and a radius of 9? x2 + y2 = 81 Example 2: What is the radius of the circle with equation x2 + y2 = 16? r = 4 () Example 3: Is the point (4, 11) inside, outside or on the circle defined by x2 + y2 = 130? B tell A how to tell if a point is inside the circle. A tell B how to tell if a point is outside the circle. A tell B how to check to see if a point is on the circle.
Example 3: Is the point (4, 11) inside, outside or on the circle defined by x2 + y2 = 130? RS LS 130 x2 + y2 = 42 + 112 = 16 + 121 = 137 Since LS > RS then (4, 11) is outside the circle x2 + y2 = 130 A tell B the 2 formulas for the circumference of a circle. B tell A the formula for the area of a circle.
A good thinking question Name 12 points on the circle x2 + y2 = 25 where x, y I (0, 5) (3,4) (4,3) (5, 0) (-3,4) (-4,3) (0, -5) (3, -4) (4,-3) (-5, 0) (-3,-4) (-4,-3) Properties of Quadrilaterals
Draw a well labelled diagram of a Rhombus Parallelogram Rectangle Square trapezoid Leave space after each shape to write a definition.
A rhombus has all 4 sides equal in length (so use the distance formula to find the lengths) and adjacent sides do not meet at right angles (so find the slopes of all 4 sides and show that adjacent slopes are not negative reciprocals and opposite slopes are equal)
A parallelogram has 2 pairs of sides equal in length (so use the distance formula to find the lengths) and adjacent sides do not meet at right angles (so find the slopes of all 4 sides and show that adjacent slopes are not negative reciprocals but opposite slopes are equal)
A rectangle has 2 pairs of sides equal in length (so use the distance formula to find the lengths) and adjacent sides meet at right angles (so find the slopes of all 4 sides and show that adjacent slopes are negative reciprocals and opposite slopes are equal)
A square has all 4 sides equal in length (so use the distance formula to find the lengths) and adjacent sides meet at right angles (so find the slopes of all 4 sides and show that adjacent slopes are negative reciprocals and opposite slopes are equal)
A trapezoid has one pair of opposite sides parallel (so find the slopes of all 4 sides and show that one set of opposite slopes are equal) (sides are not necessarily the same length) Your homework tonight is Pg. 96 # (1 – 3)c, 4a,e, 7a, 8, 15, 17, 19 Pg. 143 # 4, 14 Pg. 150 # 4