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2 years ago

What is the sum of the counting numbers 1 - 40

2 answers:

5 0

Simply it as follows:

1 + 39 = 40
2 + 38 = 40 etc

18 + 22 = 40
19 + 21 = 40

There are 19 of these plus 40 itself . . .therefore 20 of them

20 x 40 = 800

And finally the last number not used, 20

Therefore 800 + 20 = 820

natita [175]2 years ago

5 0

820. there is a shortcut which can be used when adding consecutive numbers regardless of how big it is. it can also be done manually though

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Need help with this math problem

makvit [3.9K]

Answer:

P(x) = x^4 -16x^3 +76x^2 -72x -100

Step-by-step explanation:

The two roots 1-√3 and 1+√3 give rise to the quadratic factor ...

... (x -(1-√3))(x -(1+√3)) = (x-1)^2 -(√3)^2 = x^2 -2x -2

The complex root 7-i has a conjugate that is also a root. These two roots give rise to the quadratic factor ...

... (x -(7 -i))(x -(7 +i)) = (x-7)^2 -(i)^2 = x^2 -14x +50

The product of these two quadratic factors is ...

... P(x) = (x^2 -2x -2)(x^2 -14x +50) = x^4 +x^3(-14 -2) +x^2(50 +28 -2) +x(-100+28) -100

... P(x) = x^4 -16x^3 +76x^2 -72x -100

7 0

2 years ago

Read 2 more answers

In triangle POR, PO = 9cm and PR = 12cm. If

Olin [163]

Answer:

Area of trangle = 1÷2 (9×12×sinRpo)

23= 1÷2 (108×sinRPO)

8 0

2 years ago

Please help with this question

ioda

Answer:

$25$

Step-by-step explanation:

$\frac{5^8 \times 5^{-2}}{5^4}$

$\frac{5^{8+-2}}{5^4}$

$\frac{5^{6}}{5^4}$

$5^{6-4}$

$5^2$

$=25$

3 0

2 years ago

A track runner is eager to see if practicing helps her improve. She has plotted data on her weekly 100-meter dash times (s) as w

insens350 [35]

Answer:

$\displaystyle s = -\frac{1}{5}h + 20$

Step-by-step explanation:

Time is the dependent variable, so you set your function equal to s. Then, the correlation of the graph has a $\displaystyle -\frac{1}{5}$ rate of change [slope] from the y-intercept of $\displaystyle [0, 20],$ so we choose this answer choice.

I am joyous to assist you anytime.

4 0

2 years ago

Can I get some help? Please show your work! Thanks!

kirill [66]

Hey there,

Your question states: You have a 332 feet fencing to enclose a rectangular region. What is the maximum area.

Your correct answer would be 6,889.

Reason/explanation:

The formula that we would use is $P = 2l+2w$

$f(x)=ax^{2} +b*x+c$

$L=166=-W\\ L=83$
_____________________________________________________________

So by this, now that we know that $L=83$

We do . . . 83 × 83. . .

And you final answer would be Option A.) 6,889

Hope this helps you!

~Jurgen

6 0

2 years ago

Read 2 more answers