Area=legnth times width
if legnth=x
and
area=400
400=x times width
wait
SQUARE painting
legnth=width
width=x
400=x times x
400=x^2
sqrt both sides
20=x
answer is 20 in
equation is
400=x times x
Answer:
<h2>
45</h2>
Step-by-step explanation:

So, if the common ratio is 5 the next term is always 5 times the previous term.
<h3>9·5 = 45</h3>
7.5 min per walk around the block
Answer:
Equation: 
Solve for n: n = 112
Step-by-step explanation:
To first set up the equation, you need to look at the verbal description and translate into numbers and operations:
'three fourths a number' = 
'plus 8' = + 8
'is' =
'20 less' = - 20
'the number' = n
Put the expressions together:
'three fourths a number plus 8': 
'20 less than the number': n - 20
Set them equal to each other and solve: 
Add 20 to both sides: 
Subtract
from both sides: 
Multiply both sides by
: 
Solve for n: n = 112
Since 30 is not a square root you would use the closest square roots √25 and √36 which makes your answer 5 and 6