Answers

2014-06-12T07:24:18+08:00
Here is 1 example.
Mrs. Jacinto asked a carpenter to construct a rectangular bulletin board for her classroom. She told the carpenter that the board’s area must be 18 square feet. Suppose the length of the board is 7 ft. longer than its width.

Area = l x w
18 = x(x+7)
18 = x²+7x
18 + 49/4 = x²+7x+49/4   this is a quadratic equation.

and there are other more real life situation w/ uses quadratic equation but the solution is more complicated.
7 4 7
The Brainliest Answer!
2014-06-12T08:30:31+08:00
The length of a swimming pool is 8m longer than its width and the area is 105m².
Given: 
A=105m²
l=w+8
Solution:
A= lw
105m²=w(w+8)
0=w²+8w-105
A square garden will be planted by a border of flowers. The border will be of the same dimensions around the entire garden and the has an area of 81m².
Given:
A=81m²
Solution:
A= s²
81m²=s²
0=s²-81
The width of the blackboard is 4 less than its width. The blackboard has an area of 35m².
Given:
A=35m²
w=l-4
Solution:
A=lw
35m²=l(l-4)
0=l²-4l-35

5 4 5