Answer:
(12-7x)
Step-by-step explanation:
144 − 49x²
by observation, we can see that 144 = 12² and 49 = 7²
hence we can rewrite the equation
144 − 49x²
= 12² - 7²x²
= 12² - (7x)²
recall that the expression x² - y² = (x+y)(x-y)
hence,
12² - (7x)²
= (12 + 7x)(12-7x)
(12-7x) appears in the expression above, hence 12 -7x is a factor
Answer: D
The first: (x+6)(3x3+2x2+2x+5)
The second:
factor x+6
Cannot factor
Step-by-step explanation: hope this help
Answer:
The need to sample 76 days.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so
Now, find the margin of error M as such
In which
is the standard deviation of the population and n is the size of the sample.
How many days do they need to sample
We need to sample n days.
n is found when M = 300.
We have that 
So




Rounding up
The need to sample 76 days.
4: <BEC and <ECB are supplementary.
False, <em><BEC and <ECB are angles of triangle BCE and sum of two angles of a triangle can't be equal to 180 ( two angles of a triangle can't be supplementary). </em>
5: C is the midpoint of BD.
False: <em>It's not given C is the mid-point. So, we can't assume C is a mid point.</em>
6: <BCE and < ECD are a linear pair.
True,<em> because <BCE and < ECD are two angles on a common point on a line.</em>
7: <ABE and <EBC are complementary.
True, <em>because <ABC is a right angle and <ABE + <EBC = <ABC.</em>