Answer:
Width of rectangle = 6 m
Length of rectangle = 11 m
Step-by-step explanation:
Let width of rectangle = w
Length of rectangle = 3w-7
Area of rectangle = 66 m²
We need to find length and width of rectangle
The formula used is: 
Putting values and finding w

Solve using quadratic formula: 
We have a=3, b=-7, c=-66
Putting values and finding w

We get values of w as w=6 and w=-3.6
As we know width cannot be negative, so considering w = 6
So, Width = 6
Length = 3w-7 = 3(6)-7 = 18-7 = 11
So, Width of rectangle = 6 m
Length of rectangle = 11 m
Answer:
multiply the cost by 0.18 to get the tip amount or multiply the cost by 1.18 to get the total including tip.
Step-by-step explanation:
Answer:
The dimensions of the smallest piece that can be used are: 10 by 20 and the area is 200 square inches
Step-by-step explanation:
We have that:

Let the dimension of the paper be x and y;
Such that:


So:

Substitute 128 for Area

Make x the subject

When 1 inch margin is at top and bottom
The length becomes:


When 2 inch margin is at both sides
The width becomes:


The New Area (A) is then calculated as:

Substitute
for x

Open Brackets

Collect Like Terms



To calculate the smallest possible value of y, we have to apply calculus.
Different A with respect to y

Set

This gives:

Collect Like Terms

Multiply through by 


Divide through by 2

Take square roots of both sides



Recall that:



Recall that the new dimensions are:


So:




To double-check;
Differentiate A'




The above value is:

This means that the calculated values are at minimum.
<em>Hence, the dimensions of the smallest piece that can be used are: 10 by 20 and the area is 200 square inches</em>
B. f(x)=5(6.86x) this the correct anwser
Answer:
The percentage is 
Step-by-step explanation:
Let
x-----> the number
we have

To find the percentage multiply by 100
