SOLUTION: I have problems understanding geometry, put it with algebra , quadratic equations, I sit and cry, I just dont understand. The question is: The length of a rectangular table

Algebra ->  Rectangles -> SOLUTION: I have problems understanding geometry, put it with algebra , quadratic equations, I sit and cry, I just dont understand. The question is: The length of a rectangular table      Log On


   

Question 21409: I have problems understanding geometry, put it with algebra , quadratic equations, I sit and cry, I just dont understand.
The question is:
The length of a rectangular table top is 8 feet shorter than 5 times the width. If the area of the table top is 48 square feet, find the dimensions of the table.
Thnak you so much!!
Answer by Paul(988) About Me  (Show Source):
You can put this solution on YOUR website!
(x)(5x-8)=48
5x^2-8x=48
5x^2-8x-48=0
Use quadratic formula: x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=5, b=-8, c=-48
x+=+%28-%28-8%29+%2B-+sqrt%28+%28-8%29%5E2-4%285%29%28-48+%29%29%29%2F%282%2A5%29+
x+=+8+%2B-+sqrt%28+%2864%2B960%29%29%2F%2810%29+
x+=+8+%2B-+sqrt%28+%281024%29%29%2F%2810%29+
Simpliy X=-12%2F5 or x= 4
5(4)-8=12


Hence The dimensions are 4ft and 12ft