X=-56/3
multiply everything by 4 to cancel the fraction which will give you
3x+20=-36
then combine like terms to get
3x=-56
then divide to get x by itself to get
x=-56/3
since this is a weird decimal, leave it as an improper fraction
Answer:

Step-by-step explanation:
-The margin of error is calculated using the formula:

-We substitute the values, n=900 and ME=30 in the formula to solve for standard deviation:

Hence, the population standard deviation is 547.1125
Complete the square by adding the square of half of four to both sides (4)
x^2+y^2-4y+4=4
x^2+(y-2)^2=4