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2 years ago

Explain how you know that x^2-8x+20 is always positive. Please help.

Mathematics

1 answer:

IRISSAK [1]2 years ago

4 0

Answer:

if you rearrange to complete the square, you get (x^2-4)^2 +4

and seeing as anything squared will always be positive or zero, the lowest possible value for (x^2-4)^2 is 0, when x = 4

and 0 + 4 = 4, which is greater than 0, so positive

Step-by-step explanation:

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Graph the line with slope 2 passing through the point (1, -3).

Pepsi [2]

Answer:

2x-5=y

I'm not sure how your graphing tool works so I'll give you five or so coordinates

(-1,-7)

(1,-3)

(0,-5)

(2,-1)

(-2,-9)

Step-by-step explanation:

You first need to write an equation that you can graph

Knowing that the slope is two we can write the following equation

2x+b=y

We also know that when x=1 y=-3

This gives us 2*1+b=-3

which means that 2+b=-3

subtract 2 from both sides to figure out the b=-3

This means that the line you have to graph is 2x-5=y

4 0

2 years ago

Is b = 6 a solution to the inequality b – 3 > 5?

const2013 [10]

Answer:Hlello, my name is woods245.

So you have the problem b - 3>5 and is says that b=6.

So know the problem looks like this. 6 - 3>5.

Step-by-step explanation:

6 0

2 years ago

Find the area of this shape <br><br> please

Elena-2011 [213]

<h3> $Area \:of\: rectangle = l \times b \\ = 3 \times 6 \\ = 18 {cm}^{2}$ </h3><h3> $Area\: of\: triangle = \frac{ab}{2} \\ = \frac{4 \times 6}{2} \\ = 12 {cm}^{2}$ </h3>

Total area = 12 + 18 = 30cm²

7 0

2 years ago

Read 2 more answers

There are 15,958,866 adults in a region. If a polling organization randomly selects 1235 adults without replacement, are the s

VARVARA [1.3K]

Answer:

The selections are dependent.

Yes, they can be treated as independent (less than 5% of the population).

Step-by-step explanation:

Since the selections are made without replacement, each selection affects the outcome of the next selection and, therefore, the selections are dependent.

Although they are dependent, the selections can be treated as independent if the sample size is no more than 5% of the total population. In this case, the sample size is 1235 adults out of a population of 15,958,866 adults. The percentage represented by the sample is:

$P=\frac{12,345}{15,958.866}*100\\ P=0.077\%$

Thus the selections can be treated as independent for the purposes of calculations.

3 0

2 years ago

Mr. Rodriguez is packing bags of snacks for his children's lunchboxes. If he has 20 blueberries and 30 grapes, what is

amm1812

Answer:

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers