#### bumblebee123

##### New member

- Joined
- Jan 3, 2018

- Messages
- 20

Please can you show me step by step how to show the answer? I have substituted till I am blue in the face and still don't get the right answer.

I have a question from the quadratic equations section of GCSE. I am told:

The prism is a right-angled triangle. We have established the length of the prism is found by formula L = 1/3( E - 24x)

The surface area, A cm, of the prism is given by formula A = 12x

^{2 }+ 12Lx

A = 448 cm

E= 98 cm

Substitute these values ( A and E) into the formulae of L and A to show that x satisfies the equation 3x

^{2 }- 14x +16 =0

I have inserted L into Formula A but get nothing like I should be getting. Can someone show me how to get there please?

Thank you in advance.