Thread: Maximising a quadratic function (non-calculus).

A strip of sheet metal 30 cm wide is to be made into a trough by turning strips up vertically along 2 sides.
How many cm should be turned up at each side to obtain the greatest carrying capacity?

Help pls

Thanks in advance

Originally Posted by Sorena

A strip of sheet metal 30 cm wide is to be made into a trough by turning strips up vertically along 2 sides.
How many cm should be turned up at each side to obtain the greatest carrying capacity?

Help pls

Thanks in advance

max capacity will occur when the cross-sectional area (a rectangle) is a maximum.

let x = length of metal to be turned up on both sides

A = x(30-2x)

thank you soo much