Cloud = 12 Present = 5 Reindeer = 2 5 + 4 x 24 = 101 The answer is 18 triangles. For example: A(2,3) , B(9,7) AB = √(x2-x1)^2 + (y2-y1)^2 AB = √7^2 + 4^2 AB = √49 + 16 AB = √65 If the distance between the points A(p , 0) and B(0, p) is 10, find the possible values of p. 10 = √(0-p)^2 + (p-0)^2 10 = √(-p)^2 + (p)^2 10 = √p^2 + p^2 (10)^2 = (√2p^2)^2 100 = 2p^2 √p = √50 p = ± 7.07 Given that the coordinates of the points P and Q are (-2,6) and (9,3) respectively, find the coordinates of the point R that lies on the y-axis such that PR = QR P (-2,6) , R (0,a) PR = √(0+2)^2 + (a-b)^2 PR = √4 + a^2 – 12a +36 PR = √a^2 –12a + 40 QR = Q (9,3) , R (0,a) QR = √(0-4)^2 + (a-3)^2 QR = √81 + a^2 – 6a + 9 PR = QR √a^2 –12a + 40 = √a^2 –6a + 90 -12a + 40 = -6a + 90 -90 + 40 = -6a + 12a -50 = 6a a = - 50/6 a = - 25/3 ∴ R (0, -25/3) Equation of Line y = mx + c Gradient y - intercept e.g # 1: P is the point (2,9) and Q is the point (4,6) Find the equation of the line. Gradient = (6 – 9) / (4 - 2) = -3/2 Y – Intercept: P(2,9) y = mx + c y = -3/2 x + c 9 = -3/2 (2) + c c = 12 y = -3/2 x + 12 A line has 2 points A (9,0) B (4,8). Find the gradient and y – intercept of the line. M=8–0/4–9 M = 8 / -5 M = - 8/5 OR M = -1.6 Y = mx + c 4 = ¼ (2) + c 4=½+c 4 = (1 + 2c) / 2 4 * 2 = 1 + 2c 8 – 1 = 2c C = 7/2 A line: y = -x + c passes through (1,2). Find the y – intercept (value of c). Y = -x + c 2 = - (1) + c 2+1=c C=3