You plant a 14 inch Spruce Tree that grows 4 inches per year and an 8 inch hemlock tree that grows 6 inches per year. After how many years will the trees be the same height? How tall will each be?
Please explain this to me, I don't know how to write a linear system with this.
I've come up with 14 + 4x = (dunno) and 8 + 6x(should it be a y?) = (dunno) Anyone help please?
2006-11-01 14:24:40 · 7 answers · asked by tehmonkii 2 in Science & Mathematics ➔ Mathematics
After the first 2 answers, I have:
14+4x=8+6x
-8 -8
--------------------
6+4x =6x
-4x =-4x
--------------------
6=2x
3=x
3 Years? Please correct me if I'm wrong
2006-11-01 14:40:49 · update #1
You are on the right track. Now just set the two equations equal to each other. Since you are looking for the same x you can do that. 14+4x=8+6x 6=2x x=3. Now go back and check it at 4 inches per year for 3 years the spruce will grow 12 inches to be 26 the hemlock will grow 18 to be 26.
2006-11-01 14:36:15 · answer #1 · answered by theresacra 2 · 0⤊ 0⤋
Let x = the number of years the trees grow.
Then the spruce will grow at the rate of 14 +4x and the hemlock according to 8 +6x.
Set these two expressions equal to find x when trees are same height. Thus:
14+4x=8 + 6x
2x = 6
x=3
each tree will be 26 " high
2006-11-01 14:39:51 · answer #2 · answered by ironduke8159 7 · 0⤊ 0⤋
You need to know when they will be equal, so just set them equal to each other and solve for x (number of years).
14 + 4x = 8 + 6x
3 = x
To find out how tall each tree will be, just plug in 3 to either equation, 14 + 4x or 8 + 6x.
14 + 4(3) = 26
8 + 6(3) = 26
So therefore, after 3 years your Spruce tree will be 26 inches.
2006-11-01 14:41:59 · answer #3 · answered by Devin J 2 · 0⤊ 0⤋
Why not create a chart to help you?
Let S = Spruce
Let H = Hemlock
Let x = years from now
..........Length of tree..........Growth each year.....Years From Now
S =........14 inches..................4 inches.......................x
H =..........8 inches...................6 inches......................x
Now we have:
14 + 4x = 8 + 6x
Solving for x, we get 3 years.
The answer to question a is 3 years.
How tall will each tree be?
Think about it.
Replace x with 3 in the equation I set up.
14 + 4(3) = 26 inches.
The answer must be the same for the other terms.
8 +6(3) = 26
The answer to question b is, each tree will be 26 inches.
Why 26 inches?
The orginal word problem told us that the trees would be the same size.
Guido
2006-11-01 14:41:48 · answer #4 · answered by Anonymous · 0⤊ 0⤋
14 + 4X = 8+6X
yup, that's the right answer.
X is your number of years. No need for a Y
2006-11-01 14:33:37 · answer #5 · answered by candy2025 2 · 0⤊ 0⤋
Set these equal and solve for x.
H = 14 + 4x
H = 8 + 6x
2006-11-01 14:38:50 · answer #6 · answered by powhound 7 · 0⤊ 0⤋
i thinki 14+4x one is correct
but dont depend on me. i did this a long time ago and didnt really understand it
2006-11-01 14:30:56 · answer #7 · answered by Anonymous · 0⤊ 0⤋