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.
Answer:
7 years
Step-by-step explanation:
Given that:
Let Richard's age = x
Elder sister's age = 2x
Youngwr sister's age = x - 2
Product of sisters ages = 70
2x * (x - 2) = 70
2x² - 4x = 70
2x² - 4x - 70 = 0
x² - 2x - 35 = 0
x² - 7x + 5x - 35 = 0
x(x - 7) +5(x - 7) = 0
(x - 7) or (x + 5) = 0
x = 7 or x = - 5
X can't be negative
Hence, x = 7
Richard is 7 years
Answer:
12705
Step-by-step explanation:
The problem could be solved in two different methods:
1:
231×(55)=12705
2.
231×40+231×15=9240+3465=12705
Answer:
I believe it's 4,080
Step-by-step explanation:
you just add the two numbers