Answer:
36mm
Explanation:
Ok so, here is what you do the 10mm and the 4mm you subtract them to get 6 then you will use 6 for the base of the triangle since, when we subtracted we got the rest for the bottom base of the triangle. Then we do 6 times 12 and we get 72. We divide 72 divided by 2 and get 36 and that is your answer 36mm.