PLEASE ANSWER QUICK

Fine the sum of the first 8 terms of the arithmetic series 2+7+12+...

ss7ja [257]

Answer:

156

Step-by-step explanation:

s8 = n/2 [2t + (n-1)(d)]

= 8/2 [2(2) + (8-1)(5)]

= 4 [4 + (7)(5)]

= 4 (4 + 35)

= 4 (39)

= 156

4 0

3 years ago

In the centerville during the month of February the sun didn’t shine on 75% of

melomori [17]

Hey there
So you can find the answer by dividing 28/4 which will get you 7 so we now multiple 7 By three so that we can find what 3/4 of 28 is which equals 21 days so the sun didn't sine for 21 days.

6 0

3 years ago

Read 2 more answers

F(x)= x(x+3)(x+1)(x-4) has zeros at x=-3

anygoal [31]

Answer: C) Sometimes positive; sometimes negative

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Explanation:

Pick a value between x = -1 and x = 0. Let's say we go for x = -0.5

Plug this into f(x)

f(x) = x(x+3)(x+1)(x-4)

f(-0.5) = -0.5(-0.5+3)(-0.5+1)(-0.5-4)

f(-0.5) = -0.5(2.5)(0.5)(-4.5)

f(-0.5) = 2.8125

We get a positive value.

This shows that f(x) is positive on the region of -1 < x < 0

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Now pick a value between x = 0 and x = 4. I'll use x = 1

f(x) = x(x+3)(x+1)(x-4)

f(1) = 1(1+3)(1+1)(1-4)

f(1) = 1(4)(2)(-3)

f(1) = -24

Therefore, f(x) is negative on the interval 0 < x < 4

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In short, f(x) is both positive and negative on the interval -1 < x < 4

It's positive when -1 < x < 0

And it's negative when 0 < x < 4

4 0

2 years ago

Which of the following combined with the equation −9x + 3y = 12 creates a system of linear equations with no solution?

PolarNik [594]

ANSWER

The correct answer is option A

EXPLANATION

A line that will create a system of equation with no solution when combined with
$- 9x + 3y = 12$
,is the line that has the same slope as
$- 9x + 3y = 12$
but different y-intercept.

So, let us write the given equation in slope intercept form to obtain,

$3y = 9x + 12$

$\Rightarrow \: y = 3x + 4$

The slope is
$3$
and y-intercept is
$4.$

Now let us determine the slope and intercept for the given options too.

For option A,

$18x - 6y = 20$

$\Rightarrow \: - 6y = - 18x + 20$

$\Rightarrow \: y = 3x - \frac{10}{3}$

This has the same slope as the given equation but different y-intercept. When combined with the given equation, there will be no solution, since the two lines will never intersect. so it is the correct option.

For option B,

$3x - y = - 4$

$\Rightarrow \: -y = - 3x - 4$

$\Rightarrow \: y = 3x + 4$

This option has the same slope and y-intercept as the given line so when combined with this equation, there will be infinitely many solution.

As for option C and D they do not have the same slope as the given line so there will be a unique solution when each is combined with the given line.

8 0

3 years ago

Can someone please help me?

Kamila [148]

Answer:

(3)

Step-by-step explanation:

5 0

3 years ago