Soccer Question

Question

The posts of a soccer (football) net are 7.50 m apart. A player is about to kick the ball to the net. If the ball is approximately 15 m from one post and 20 m from the other, within what angle does the player have to kick the ball for it to go into the net? (4 marks)

Answer 1

Can use Law of Cosines when 3 sides of triangle are known.

In this case the sides are 20, 15 and 7.5. We need the angle opposite the goal posts, Let's call that Angle C, and the side opposite that angle (c) = 7.5m. The other two sides (a and b) are 15m and 20m.

cosC = (c² - a² - b²)/-2ab.

If you substitute the values and use a table or scientific calculator, you will get the value for angle C.