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3 years ago

I need a bit of help pls.

Mathematics

1 answer:

Gnesinka [82]3 years ago

6 0

Answer:

#1. 150, #2. 650, #3. 2 PM to 4 PM #4. 8AM to 4PM (8 hours) #5. the frequency of weight in pounds #6. 22 cats

#7. 1 - 40 pounds #8. 11 - 20 pounds

You might be interested in

When graphing y = 2x2 + 35x + 75, which viewing window would allow you to see all of the intercepts and the minimum as closely a

djverab [1.8K]

The intercept with the y-axes occurs when x = 0

f(0) = 2*02 + 35*0 + 75 = 0 + 0 + 75 = 75

So intercept with x axes is the point (0,75)

The intercept with the x-axes occurs when y=0

2x2 + 35x + 75 = 0

As there’s no direct way to find x, we can use the Bhaskara formula:

x=(-b+- square root (b2-4ac))/(2a)

This formula is for: ax2 +bx + c = 0

So:

a=2

b=35

c=75

x=(-35+- square root (35^2-4*2*75))/(2*2)

So x can be -2.5 or -15

So intercept with y axes are the points (-2.5,0) and (-15,0)

And there is also a formula to find the mínimum. The mínimum is always the vertex:

Xv = -b/(2*a) = -35/(2*2) = -8.75

Yv = f(Xv) = f(-8.75) = 2(-8.75)^2 + 35(-8.75) + 75 = -78.125

So the minimum is the point (-8.75, -78.125)

You can easily verify all these data with a graphic software such as GeoGebra.

Here is the complete list of all the points we need to see:

(0,75); (-2.5,0) ; (-15,0), (-8.75, -78.125)

So the mínimum X has to be -15 and the máximum X has to be 0

and the mínimum Y has to be -78.125 and the máximum Y has to be 75

So this leads to a different scale for X and for Y.

Window x = [ -15, 0] y = [ -78.125, 75]

5 0

3 years ago

Plz help me plz plz plz its math

notka56 [123]

Answer:

I hope this help you

Step-by-step explanation:

3 0

3 years ago

Kelly bought a book of 20 stamps. She has used 80% of them. A. How many stamps has Kelly used? B. How many stamps does she have

jok3333 [9.3K]

80% of 20 is 80/100 x 20 = 16

So, kelly has used 16 stamps, and has 4 left

4 0

3 years ago

Read 2 more answers

6. The diagram on the right shows the cross-section of a cylindrical pipe with water lying in the bottom. a) If the maximum dept

riadik2000 [5.3K]

Answer:

404 cm³ Anyway... Look down here for my explanation.

Step-by-step explanation:

Let's Draw a line from the center of the circle to one of the ends of the chord (water surface) and another to the point at greatest depth on your paper. A right-angled triangle is formed too. The Length of side to the water-surface is 5 cm, the hospot is 7 cm.

We Calculate the angle θ in the corner of the right-angled triangle by: cos θ = 5/7 ⇒ θ = cos ˉ¹ (5/7)

44.4°, so the angle subtended at the center of the circle by the water surface is roughly 88.8°

The area shaded will then be the area of the sector minus the area of the triangle above the water in your diagram.

Shaded area 88.8/360*area of circle - ½*7*788.8°

= 88.8/360*π*7² - 24.5*sin 88.8°

13.5 cm²

(using area of ∆ = ½.a.b.sin C for the triangle)

Volume of water = cross-sectional area * length

13.5 * 30 cm³

404 cm³

6 0

2 years ago

Question 7

serg [7]

$\huge\underline{\red{A}\blue{n}\pink{s}\purple{w}\orange{e}\green{r} -}$

Given - a cone with volume 769?3 ft³ , having a height of 15 ft

To calculate - radius of the cone

We know that ,

$\bold{Volume \: of \: cone = \frac{1}{3}\pi \: r {}^{2} h }\\$

substituting the values in the formula stated above ,

$\bold{769.3 = \frac{1}{3} \times 3.14 \times r {}^{2} \times 15} \\ \\\bold{\implies r {}^{2} = \frac{769.3 \times 3}{3.14 \times 15} } \\ \\\bold{\implies r {}^{2} = \cancel\frac{2307.9}{47.1}} \\ \\\bold{ \implies \: r {}^{2} = 49} \\ \\ \bold{\implies \: r = 7 \: ft}$

therefore ,

radius = 7 cm

hope helpful ~

4 0

2 years ago