2x-4y=-16
ax+4y=6 +
--------------------
2x+ax=-10; for x=-2,
2(-2)+a(-2)=-10
-2a=-10+4
a=-6/-2
a=3
Answer:
your answer should be 48 degrees
The surface area is 169.65ft^2
To solve this problem, we make use of the z statistic.
The formula for the confidence interval can be calculated using the formula:
Confidence Interval = p ± MOE
where,
p is the portion of girls = 278 / 556 = 0.5
MOE is the margin of error
We calculate the margin of error using the formula:
MOE = z * sqrt[p (1 – p) / n]
From the standard distribution tables, the value of z at 99% confidence is:
z = 2.58
Therefore the MOE is:
MOE = 2.58 * sqrt[0.5 (0.5) / 556]
MOE = 0.055
Therefore the confidence interval is:
Confidence Interval = 0.5 ± 0.055
Confidence Interval = 0.445, 0.555
0.445<p<0.555