Given:
The equation is
[tex]y=x^2+2x+1[/tex]
where y is the total square inches of tissue paper and x is the side length of the canvas in inches.
To find:
The side length of the canvas is Martha needs 49 square inches of tissue paper.
Solution:
We have,
[tex]y=x^2+2x+1[/tex]
Putting y=49, we get
[tex]49=x^2+2x+1[/tex]
[tex]0=x^2+2x+1-49[/tex]
[tex]0=x^2+2x-48[/tex]
Splitting the middle term, we get
[tex]0=x^2+8x-6x-48[/tex]
[tex]0=x(x+8)-6(x+8)[/tex]
[tex]0=(x+8)(x-6)[/tex]
Using zero product property, we get
[tex]x+8=0[/tex] and [tex]x-6=0[/tex]
[tex]x=-8[/tex] and [tex]x=6[/tex]
Side length cannot be negative. So, only possible value of x is 6.
Therefore, Martha needs 6 inches side length of the canvas for 49 square inches of tissue paper.