6. The length, of a solid is inversely proportional to the square of its height, y, x. (a) Write down a general equation for and x y. Show that when = 5 and = 4.8 the equation becomes = 120. x y x2 y [2] (b) Find when = 2. y x [1] (c) Find when = 10 x y [2] (d) Find when = x y x. [2] (e) Describe exactly what happens to when is doubled. y x [2] (f) Describe exactly what happens to when is decreased by 36%. x y [2]
6. The length, y, of a solid is inversely proportional to the square of its height, x. (a) Write down a general equation for x and y. Show that when x = 5 and y = 4.8 the equation becomes x2 y = 120. [2] (b) Find y when x = 2. [1] (c) Find x when y = 10 [2] (d) Find x when y = x. [2] (e) Describe exactly what happens to y when x is doubled. [2] (f) Describe exactly what happens to x when y is decreased by 36%. [2]
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