PLEASE PLEASE PLEASE HELP I NEED IT What is the sum of the series?

Mathematics

1 answer:

JulsSmile [24]4 years ago

7 0

Formula :

$n\left(a_1+\frac{d\left(n-1\right)}{2}\right)$

Plug in the values :

$20\left(1+\frac{-3\left(20-1\right)}{2}\right) = 550$

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Answer:550
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Find two positive numbers so that twice their sum equals their product and one number is 10 times the other number. Enter the sm

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Answer:

Step-by-step explanation:

We'll call the 2 numbers x and y. Starting with the last part of that first sentence "one number is 10 times the other number" can be written, in algebraic form:

y = 10x

Now on to the first statement about the numbers: "twice their sum" is 2(x + y) and "equals their product" is = xy. Putting that all together:

2(x + y) = xy and we know that y = 10x so

2(x + 10x) = x(10x) and

$2(11x)=10x^2$ and