Problema Solution
A window maker has 25 feet of wire to frame a window. One side of the window is "x" feet and the other side is "9-x" feet.
a. Write an equation to represent the area "A" of the window.
b. If the area of the window is 18 square feet, what are the two possible values of "x"?
Answer provided by our tutors
1).the area A = x * (9-x)
= 9x - x^2
2). the area of the window is 18 square feet
18 = 9x - x^2
x^2-9x+18 = 0
x = [-b+-sqrt(b^2-4ac)]/2a
where a =1 , b = -9 ,c =18
so x1 = [9+i3]/2
x2 = [9-i3]/2