The width of a rectangle is 9 in. shorter than its length. The area of the rectangle is 252 in². What is the length of the rectangle? Enter your answer in the box. in

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Answer:

the length of the rectangle is, 21 in.

Step-by-step explanation:

Area of the rectangle(A) is given by:

[tex]A=lw[/tex]           .....[1]

where,

l is the length of the rectangle

w is the width of the rectangle.

As per the statement:

The width of a rectangle is 9 in. shorter than its length.

⇒[tex]w = l-9[/tex]

It is also given that:

The area of the rectangle is 252 in².

⇒A = 252  in².

Substitute in [1] we have;

[tex]252 = l(l-9)[/tex]

⇒[tex]252 = l^2-9l[/tex]

⇒[tex]l^2-9l -252 = 0[/tex]

Factorize this equation:

Split the middle term;

⇒[tex]l^2-21l+12l-252=0[/tex]

⇒[tex]l(l-21)+12(l-21)=0[/tex]

⇒[tex](l-21)(l+12)=0[/tex]

By zero product property we have;

[tex]l-21 =0[/tex] and [tex]l+12 =0[/tex]

⇒[tex]l = 21[/tex] and [tex]l = -12[/tex]

Since, length cannot be in negative

⇒[tex]l = 21 in.[/tex]

Therefore, the length of the rectangle is, 21 inches.

Answer:

The length of the rectangle is 21 in.

Step-by-step explanation:

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