Gary works at a bakery, and he needs to select a rectangular cookie sheet with an area of 192 square inches. the area of the cookie sheet is represented by the expression given below. x² + 4x complete the given statements, and find the width of the cookie sheet. step 1: x² + 4x = 192 step 2: x(x + ) = 192 the length is x. the width is step 3: x² + 4x = 192 = 0 step 4: (x + ) (x - 12) = 0 because the length can't be the length is 12, and the width is here is the selection of values that can be inserted into the blank spaces. note that not all of them will be used. 12 4 x x + 4 -16 16 x + 12 x²

 
x-------> the length of a rectangular cookie sheet

we know that
area of a rectangular cookie sheet=length*width
area of a rectangular cookie sheet=192 in²
area of a rectangular cookie sheet=x² + 4x-----> x*(x+4)

Step 1: x² + 4x = 192
Step 2: x(x + 4 ) = 192 The length is x. The width is (x+4)
Step 3: x² + 4x = 192=0
we have 
x² + 4x = 192
x² + 4x - 192=0
using a graph tool-----> to resolve the second order equation
see the aattached figure
the solution is 
x=-16
x=12
(x+16)*(x-12)=0

the length is x=12 in
and the width is-----> (x+4)-----> 12+4----> 16 in

Step 4: (x +16) (x - 12) = 0
Because the length can't be -16  the length is 12, and the width is 16