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.
But you're already done....
Answer:
25
Step-by-step explanation:
8*5=40
40+6=46
46-10=36
36-9=25
We can say that x is the largest number.
So the sum is x + (x - 1) + (x - 2) + (x - 3) + (x - 4) = -5
Now solve for x:
x + x + x + x + x - 1 - 2 - 3 - 4 = -5
5x - 10 = -5
5x = 5
x = 1
So the largest number is 1.
Check: 1 + 0 + -1 + -2 + -3 = -2 + -3 = -5 so 1 is correct.