Question

Please help. I need this urgently
Please no links please​

Answer 1

Look below

Explanation:

(a) The area of a triangle is:

`A=(1)/(2)bh`

The height of this triangle is h and it's base is 4+h so...

`A=(1)/(2)*[h*(h+4)]`

`A=(1)/(2)*(h^2+4h)\\A=(h^2)/(2)+2h`

(b) If the height is 8 cm, then the base is 4+8 which is 12 cm so...

`A=(1)/(2)*8*12=4*12=48 \ cm^2`