Acompany wishes to manufacture some boxes out of card. the boxes will have 6 sides (i. e. covered at the top). they wish the boxes to have a volume of 200 cm^3. what dimensions should they make the boxes in order to minimise the amount of card used? you can connect the sides of the box. you should marks they are assume no flaps are required to use the hessian matrix to prove this is indeed a minimum. [10

The figure shows triangle def and line segment bc, which is parallel to ef: triangle def has a point b on side de and point c on side df. the line bc is parallel to the line ef. part a: is triangle def similar to triangle dbc? explain using what you know about triangle similarity. part b: which line segment on triangle dbc corresponds to line segment ef? explain your answer. part c: which angle on triangle dbc corresponds to angle f? explain your answer. asap