solving Quadratic Equations/ WORD PROBLEMS

12344321 · #1 Mar 2, 2007, 05:40 AM

I HAVE NO IDEA HOW TO DO SOMTHINGLIKE THIS????

The length of a rectangle is 2 feet more than the height. the area of the rectangle is 5 foot , find the base??

mloda492 · Nov 8, 2007, 06:54 PM

The length of a rectangle is 2 feet more than the height. the area of the rectangle is 5 foot , find the base??

Quote:

Originally Posted by Capuchin

here you need to solve simultaneous equations

Now you can rearrange the first equation for h, put it into the second equation, then solve for l and that should be the base youa re looking for.

Let me know if you get stuck.

i am stuck.

terryg752 · Nov 9, 2007, 02:58 AM

(WHY use 2 variables and make it harder to solve?)

(One variable can do the job and obviate the need of simultaneous equation)

Let me try to explain:

Suppose length is L (as we want to find value of length).

Then height has to be L - 2

So the area = Length times height = 5

L (L - 2) = 5

L^2 - 2L - 5 = 0

Solve this quadratic equation to get the Length L.

You get 2 roots of this equation, one root is negative.

As Length cannot be negative, ignore the negative root of the quadratic.



At Ask Me Help Desk you can ask questions in any topic and have them answered for free by our experts. To ask questions or participate in answering them you must register for a free account. By registering you will be able to: Get free answers from experts in any of our 300+ topics. Accept money for answers that you provide. Communicate privately with other members (PM). See fewer ads. Sign Up!