Answer: 
Step-by-step explanation:
The perimeter of a rectangle can be calcualated with this formula:
Where "l" is the lenght and "h" is the height.
The area of a rectangle can be found with this formula:
Where "l" is the lenght and "h" is the height.
In this case we know that:
Therfore, we can susbsitute them into and solve for "h" in order to find its value:
Find two number whose sum is 3 and whose product is -40. These are -5 and 8. Then, factorizing, we get:
The positive value is the height. Then:
Since the length is 3 centimeters greater than its height, we get that this is: Then:
Substituting values into , we get that the perimeter is:
I think that there are 33 left.
I hope this helps you!
Answer:
Step-by-step explanation:
Explanation:
Start by writing out your starting expression
x
2
−
5
x
2
+
5
x
−
14
−
x
+
3
x
+
7
Next, factor the denominator of the first fraction
x
2
+
5
x
−
14
x
2
+
7
x
−
2
x
−
14
x
(
x
−
2
)
+
7
(
x
−
2
)
(
x
−
2
)
(
x
+
7
)
Your expression is thus equivalent to
x
2
−
5
(
x
−
2
)
⋅
(
x
+
7
)
−
x
+
3
x
+
7
Since you have to subtract two fractions, you need to find the commonon denominator first. To do that, multiply the second fraction by
x
−
2
x
−
2
x
2
−
5
(
x
−
2
)
⋅
(
x
+
7
)
−
(
x
+
3
)
⋅
(
x
−
2
)
(
x
−
2
)
⋅
(
x
+
7
)
This will get you
x
2
−
5
−
(
x
+
3
)
(
x
−
2
)
(
x
−
2
)
(
x
+
7
)
x
2
−
5
−
x
2
−
x
+
6
(
x
−
2
)
(
x
+
7
)
=
1
−
x
(
x
−
2
)
(
x
+
7
)
I think the correct answer is c
Formula for Perimeter of Rectangle:
P = 2(L + W)
Plug in 160:
160 = 2(L + W)
L = 4W
So we can plug in '4W' for 'L' in the first equation.
<span>160 = 2(L + W)
160 = 2(4W + W)
Combine like terms:
160 = 2(5W)
160 = 10W
Divide 10 to both sides:
W = 16
Now we can plug this back into any of the two equations to find the length.
L = 4W
L = 4(16)
L = 64
So the width is 16, and the length is 64.</span>
