weezie79
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The length of a rectangle is 4 inches more than its width, and its perimeter is 34 inches. Find the length and width of the rectangle. If w= the width of the rectangle, then the length equals OW-4 OW-4 401​

Respuesta :

length is
10.5
inches
width is
6.5
inches
Explanation:
Let length be
l

Let width be
w

Let perimeter be
P

First, we must construct an equation for these variables:
l
=
w
+
4

P
=
34

But, Perimeter of a rectangle
=
l
+
w
+
l
+
w

=
2
l
+
2
w

So:
34
=
2
l
+
2
w

But, since
l
=
w
+
4
, we can substitute for
l
, having only the
w
variable:
34
=
2
(
w
+
4
)
+
2
w

34
=
2
w
+
8
+
2
w

34
=
4
w
+
8

Solve for
w
:
4
w
=
34
−
8

4
w
=
26

w
=
26
4

w
=
6.5
inches
Now, we can substitute
6.5
for
w
in the Perimeter Equation:
34
=
2
l
+
2
w

becomes:
34
=
2
l
+
2
⋅
6.5

34
=
2
l
+
13

Solve for
l
:
2
l
=
34
−
13

2
l
=
21

l
=
21
2

l
=
10.5
inches
Thus, length is
10.5
inches
Thus, width is
6.5
inches

Answer: L = 4 + w

A = 2P - 4

lw = 2(2l +2w) - 4

lw = 4(l + w) - 4

(w+4)w = 4 ( w+4+w) -4

(w +4)w = 4(2w + 4) - 4

w^2 + 4w = 8w + 16 - 4

w^2 + 4w = 8w + 12

w^2 - 4w - 12 = 0

( w - 6 )( w + 2 ) = 0

w - 6 = 0 ----> w = 6 ----> L=10 ---> P = 32 and A = 60

w + 2 = 0 ---> w = -2 <--- width cannot be negative; disqualified/rejected

Step-by-step explanation:

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