Answer:

Step-by-step explanation:
We know that the length is four times the width, so:

We also know the area, which is 324 m². The formula for area:

Insert the known values:

Solve for w. Simplify by removing parentheses:

Divide 4 from both sides to isolate the variable:

Find the square root of both sides:

The width is 9 m.
We know the width. Now find the length by using the area formula and inserting known values:

Solve for l. Divide both sides by 9:

The length of the rectangle is 36. (You can check: 4 times 9 is 36)
Now find the perimeter:

Insert values:

The perimeter is 90 m.
Plan A: 30 + 0.01m
Plan B: 20 + 0.05m
in order for 2 plans cost the same, both need to be equal
so should be
20 + 0.05m = 30 + 0.01m
answer is D. last one
20 + 0.05m = 30 + 0.01m
Answer:
Step-by-step explanation:
Rationalize the denominator of b. So, multiply the numerator and denominator by 

Now, find a +b

Combine like terms

Now find (a + b)²
(a +b)² = 

Hint: 
Step-by-step explanation:
0.6x- 1.2x = 6
-0.6x = 6
x = 6/0.6
x = -10