A rectangle has an area of 208 square inches. The width is 2 more than 3 times the length. Find the length and width, in inches, of the rectangle.

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EXPLANATION:

Given;

We are given the following information. A rectangle has an area of 208 square inches. The width is 2 more than 3 times the length.

Required;

We are required to find the length and the width.

Step-by-step solution;

If the length is given as l, then the width would be 2 plus 3 times l. That is;

[tex]\begin{gathered} If\text{ } \\ length=l \\ Then \\ width=2+3l \end{gathered}[/tex]

Note also that the area of a rectangle is calculated as;

[tex]Area=l\times w[/tex]

Given that the area is 208 square inches, we can set up the following information;

[tex]\begin{gathered} Area=l\times w \\ Therefore: \\ 208=l(2+3l) \end{gathered}[/tex]

We simplify the parenthesis;

[tex]208=2l+3l^2[/tex]

We can move all terms to one side of the equation and we have;

[tex]3l^2+2l-208=0[/tex]

Now we have a quadratic equation and we shall solve this by the quadratic equation formula.

[tex]x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]

The variables in this case are;

[tex]a=3,b=2,c=-208[/tex]

We can now substitute these into the quadratic formula and solve as follows;

[tex]x=\frac{-2\pm\sqrt{2^2-4(3)(-208)}}{2(3)}[/tex][tex]x=\frac{-2\pm\sqrt{4+2496}}{6}[/tex][tex]x=\frac{-2\pm\sqrt{2500}}{6}[/tex][tex]x=\frac{-2\pm50}{6}[/tex]

We can now evaluate separately as follows;

[tex]\begin{gathered} x_1=\frac{-2+50}{6}=\frac{48}{6}=8 \\ Also: \\ x_2=\frac{-2-50}{6}=\frac{-52}{6}=-\frac{26}{3} \end{gathered}[/tex]

Therefore, the two values of l will be,

[tex]\begin{gathered} l_1=8in \\ l_2=-\frac{26}{3}in \end{gathered}[/tex]

We shall take the positive value only, since we know that the length or width of any plane shape is always a positive value.

Therefore, the length of the rectangle is 8 inches. The width can now be determined as follows;

[tex]w=2+3l[/tex][tex]w=2+3(8)[/tex][tex]w=2+24=26[/tex]

Therefore;

ANSWER:

[tex]\begin{gathered} length=8in \\ width=26in \end{gathered}[/tex]