Use the next formula to find the margin or error:

z is the critical value (For a 95% confidence level the z-score is 1.95998)
σ is the standard deviation
n is the sample size

<h2>Then the margin of error is: 6.6639</h2>
I NEED BOINTS IM
SORRY GOOD LORD BUTTTTTTT MAYBE C
Answer:
x=3 because you have to multiply by the reciprocal on both sides which leaves you with 30/10 and simplified it is 3
You problem is you don't have any problem. You have a bunch of formulas for the perimeter and area of some shapes.
As for using the formulas, usually you're given all but one of the variables and you can solve for the remaining one.
Notice how the triangle result doesn't have area as a function of a, b and c. That's called Heron's formula and is usually not taught to secondary school students. I don't like to teach it either because Archimedes' Theorem is so much better:
The sides a,b,c and area S of a triangle satisfy

.7 and 7 are related because:
-If you move the decimal point left or right depending, they are the same number.
-They both stand for a value.
-They are both rational. They can both be put into a ratio or fraction.
I hope this helps!
~kaikers