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3 years ago

Please help thank you very much

Mathematics

1 answer:

sineoko [7]3 years ago

8 0

Answer:

lower right

Step-by-step explanation:

Part 1

Givens

a1 = - 20

d = +4

n = 30

Equation

a30 = a1 + (n - 1)d

Solution

a30 = -20 + (30 - 1)*4

a30 = -20 + 29*4

a30 = - 20 + 116

a30 = 96

=====================

Part 2

Formula

Sum = (a1 + L)*n/2

n = 30

So only the two on the right can be considered

a1 = -20

L = 96

Sum = (-20 + 96)30/2 is the bottom right. D if you think of it that way.

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Step-by-step explanation:

Let l = length, w = width, A = area = l×w , and P = perimeter = 2(l+w)

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solving

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$x-\frac{11}{2}=-\sqrt{\frac{289}{4}}$

$x-\frac{11}{2}=-\frac{17}{2}$

$x-\frac{11}{2}+\frac{11}{2}=-\frac{17}{2}+\frac{11}{2}$

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x = 14, or x = -3

As the width 'x' can not be negative.

so x = 14

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The width = x = 14

The length = x+5 = 14+5 = 19

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