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

Taking the square root of both sides gives two possible cases,

or

Recall that

If
and
, we have

so in the equations above, we can write

Then in the first case,


(where
is any integer)


and in the second,




Then the solutions that fall in the interval
are

-5x-6.5>12
Add 6.5 to both sides...
-5x>18.5
Divide both sides by -5 and flip the sign...
x<-3.7
Answer:
Explanation:
<u>1. Calculate the average speed of train B</u>
- 60mph = 3/4 (s) ⇒ s = 60 (4/3) mph = 80 mph
<u>2. Build a table</u>
When the two trains meet:
Train Average speed Distance time (distance/average speed)
mph
A 60 x x/60
B 80 240 - x (240 - x) / 80
<u>3. Write the equation</u>
The time, when the two trains meet, is the same for both trains:

<u>4. Calculate the time:</u>
- x/60 = 102.86 / 60 = 1.7 hours
The two trains will meet after 1.7 hours