Answer: The height of each fir tree is 9 meters, and the height of each pine tree is 12 meters.
Step-by-step explanation:
Let x= height of each fir tree, y = height of each pine tree.
As per given, we have
x+y = 21 (i)
4x=y+24 (ii)
From (ii),
(iii)
Add (i) and (iii), we get

Put value of x in (i), we get

Hence, the height of each fir tree is 9 meters, and the height of each pine tree is 12 meters.
I am sorry i have no idea. :( But i can ask my brother who is in a higher grade than i. i will ask him when he gets home for you. :)
Answer:
170 square inches
Step-by-step explanation:
triangle = 1/2 Base * height
1/2 *20 * 17 = 170 in^2