The bed of a pond can be modeled by 30y=x^2-14x+13, where x and y are measured in meters and the x-axis matches the water level of the pond. What is the width of the pond?
I seriously don't get this one and any help toward solving it would be great.
2006-08-02 06:17:57 · 9 answers · asked by Anonymous in Education & Reference ➔ Homework Help
Sorry for my poor English:
Draw a graph this function:
y = 1/30x^2 - 14/30x + 13/30
Now make the area between the graph and the x-axis blue.
This is the pond.
To determine the width of the pond, you have to calculate the point where the graph crosses the x-axis.
For all point on the x-axis: y=0
So: 1/30x^2 - 14/30x + 13/30 = 0
So: x^2 - 14x + 13 = 0
So: (x+14)(x-1) = 0
So x=1 or x=-14
There width of the pool is the difference between these two number: 15
2006-08-02 07:36:24 · answer #1 · answered by Anonymous · 0⤊ 0⤋
If the x-axis is the surface of the pond, then one end of the pond is the origin (0,0). Now graph the equation on a graphing calculator and find the second x-intercept, or solve the equation for y=0 (the x-axis intercepts, basically) and you'll get two answers; one is 0, the front end of the pond, and the other is the distance from the front to the back of the pond, hence the width.
Sorry I'm not doing it for you, I just show you around, you can do the actual work, since this is only homework help :)
hope you get it now.
2006-08-02 13:29:36 · answer #2 · answered by IspeakToRocks 2 · 0⤊ 0⤋
Give me a minute--there's a great algebra site that might help you.
Simplifying
30y = x2 + -14X + 13
Reorder the terms:
30y = 13 + -14X + x2
Solving
30y = 13 + -14X + x2
Move all terms containing X to the left, all other terms to the right.
Add '14X' to each side of the equation.
14X + 30y = 13 + -14X + 14X + x2
Combine like terms: -14X + 14X = 0
14X + 30y = 13 + 0 + x2
14X + 30y = 13 + x2
Add '-30y' to each side of the equation.
14X + 30y + -30y = 13 + x2 + -30y
Combine like terms: 30y + -30y = 0
14X + 0 = 13 + x2 + -30y
14X = 13 + x2 + -30y
Divide each side by '14'.
X = 0.9285714286 + 0.07142857143x2 + -2.142857143y
Simplifying
X = 0.9285714286 + 0.07142857143x2 + -2.142857143y
2006-08-02 13:25:31 · answer #3 · answered by Love2Sew 5 · 0⤊ 0⤋
30y=x^2-14x+13
y= (x^2-14x+13)/30
plug in a number for x, and you get y
If x, the depth is 1, you get
x^2 = 1-14+13=0
Something is wrong with the problem. At 1ft depth
you won't have no width.
If x=2
x^2=2(2)=4 4-28+13=-11
The problem is flawed.
2006-08-02 13:40:35 · answer #4 · answered by helixburger 6 · 0⤊ 0⤋
How old are you?? I am not doing your homeworkd for you hunny...sorry! Figure it out yourself or take it to your teacher.
2006-08-02 13:21:52 · answer #5 · answered by Atlanta M 1 · 0⤊ 0⤋
sorry babe sounds like you need to work that one out with your teacher it's a tough one
2006-08-02 13:36:37 · answer #6 · answered by worldstiti 7 · 0⤊ 0⤋
I would anwser your quest. but im in the same situation you are ..dude we go on here for help and everyones cocky about it...its " homework help" duh people..
2006-08-02 13:28:19 · answer #7 · answered by Anonymous · 0⤊ 0⤋
wait what
2006-08-02 13:22:24 · answer #8 · answered by Takumi 3 · 0⤊ 0⤋
it's a captious question, doesn't it?
2006-08-02 13:27:43 · answer #9 · answered by ь׀а ь׀а ь׀а░░▒▒░░ 2 · 0⤊ 0⤋