Answer:
A
Step-by-step explanation:
trust
Mutiply first equation by -1 and add to 2nd
-y=3x-6
<u>y=x^2-4 +</u>
0=x^2+3x-10
factor like any equation
what 2 numbers multiply to -10 and add to 3
-2 and 5
0=(x-2)(x+5)
set to zero
x-2=0
x=2
x+5=0
x=-5
solve for y in each case
for x=2
y=2^2-4
y=4-4
y=0
(2,0) is a point
for x=-5
y=(-5)^2-4
y=25-4
y=21
(-5,21) is another
the solutions are
(2,0) and
(-5,21)
Answer: 74.5% of the measurements fall within one standard deviation of the average.
Step-by-step explanation:
The total number of measurements given is 2 + 12 + 10 + 33 + 40 + 76 + 80 + 65 + 52 + 22 + 12 + 5 + 11 = 420
If the mean is 21 mm and one standard deviation is 0.23 mm, then one standard deviation from the mean would be
21 ± 0.23
The lower limit is 20.77 mm
The upper limit is 21 + 0.23 = 21.23 mm
The number of measurements that fall within this range are
20.8 × 40
20.9 × 76
21.0 × 80
21.1 × 65
21.2 × 52
The total number of measurements that fall within this range is
40 + 76 + 80 + 65 + 52 = 313
The percentage of the measurements that fall within one standard deviation of the average is
313/420 × 100 = 74.5%
Answer:
OMG you are so pretty
Step-by-step explanation:
Answer:
Then about 3/10 didn't get problem 15 wrong on Friday's math test. :)
Step-by-step explanation:
