hi i need to work out the area of a cross:

the diagram shows a cross.

all angles in the shape are made from right angles.

the length of each long side is double the length of each short side.

the length of each short side is 5cm.

this is the cross with the angles and measurements one one side:

(will post image on next post as it isn't letting me now!!!)

basically would i just do

10x5=50

50x4= 200

10x10=100

200+100+50=350cm^2???

would this be correct? if not where am i going wrong?

thanks!