Questions Discussed:
Question 7. Find the slope of the line, which makes an angle of 30° with the positive direction of y-axis measured anticlockwise.
Question 8. Find the value of x for which the points (x, – 1), (2, 1) \text{ and } (4, 5) are collinear.
Question 9. Without using distance formula, show that points (– 2, – 1), (4, 0), (3, 3) \text{ and } (–3, 2) are the vertices of a parallelogram.
Question 10. Find the angle between the x-axis and the line joining the points (3, –1) and (4,–2).
Question 11. The slope of a line is double of the slope of another line. If tangent of the angle between them is { \displaystyle \frac{1}{3} }, find the slopes of the lines.
Question 12. A line passes through { \displaystyle(x_1, y_1) } \text{ and } (h, k). If slope of the line is m, show that { \displaystyle k – y_1 = m (h – x_1) }.
Question 13. If three points (h, 0), (a, b) \text{ and } (0, k) lie on a line, show that { \displaystyle \frac{a}{h} } + { \displaystyle \frac{b}{k} } = 1.
Question 14. Consider the following population and year graph (Fig 10.10), find the slope of the line AB and using it, find what will be the population in the year 2010?
