Answer: (2x+5)(2x−5)
Step-by-step explanation:For me, what i like to do is to try divide the problem into two parts. For example in this problem, you would divide the 4x^2 into two 4x(since 4x+4x = 4x^2). Then 25 can be divide into into 5s (5x5=25). SInce you know that its a negative 25, you know that it has to be a negative on one of the sides. So the answer in factor form is (2x+5)(2x−5)
The last one is correct because 60+35+35+35=165
55+55+55=165
Answer: 35 additional teachers are needed
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Explanation:
We have 2470 students and the ratio of students to teachers is 26:1. This means that for every teacher, there are 26 students. Put another way, we can set up this ratio
2470/x = 26/1
where x is the number of teachers. Cross multiply and solve for x
2470/x = 26/1
2470*1 = 26*x
2470 = 26x
26x = 2470
26x/26 = 2470/26
x = 95
So we have 95 teachers currently
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Let y be the new number of teachers needed to bring the ratio down to 19:1
Using a similar idea as done above, we would have this ratio
2470/y = 19/1
Let's solve for y
2470/y = 19/1
2470*1 = 19*y
2470 = 19y
19y = 2470
19y/19 = 2470/19
y = 130
So we'll need 130 teachers to have the ratio be 19:1
The difference of the values is y - x = 130 - 95 = 35, which is the final answer. This is the additional amount of teachers needed.
Answer:
The Taylor series of f(x) around the point a, can be written as:

Here we have:
f(x) = 4*cos(x)
a = 7*pi
then, let's calculate each part:
f(a) = 4*cos(7*pi) = -4
df/dx = -4*sin(x)
(df/dx)(a) = -4*sin(7*pi) = 0
(d^2f)/(dx^2) = -4*cos(x)
(d^2f)/(dx^2)(a) = -4*cos(7*pi) = 4
Here we already can see two things:
the odd derivatives will have a sin(x) function that is zero when evaluated in x = 7*pi, and we also can see that the sign will alternate between consecutive terms.
so we only will work with the even powers of the series:
f(x) = -4 + (1/2!)*4*(x - 7*pi)^2 - (1/4!)*4*(x - 7*pi)^4 + ....
So we can write it as:
f(x) = ∑fₙ
Such that the n-th term can written as:

Answer:
2.25 inches
Step-by-step explanation:
The mean, or the average, or the rainfall amounts, can be found by adding all of the amounts together and dividing by the number of amounts. In this case,
. Hope this helps!