Find the volume & surface area of a cylinder with radius 4 cm and height 9 cm

Mathematics

1 answer:

Komok [63]3 years ago

7 0

Answer:

V= 452.39cm³ (to 2 d.p. )

S.A. = 326.73cm² (to 2 d.p. )

Step-by-step explanation:

Vcylinder = π r² h = π (4)² (9) = 144 π = 452.3893421cm³ = 452.39cm³ (to 2 d.p. )

S.A. cylinder = 2π r h + 2π r² = 2π (4)(9) + 2π (4)² = 104π = 326.725636cm² = 326.73cm² (to 2 d.p. )

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maksim [4K]

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Part B

The vertex will be a minimum because the coefficient of $x^2$ is positive.

The x-coordinate of the vertex is $x=-\frac{-7}{2(4)}=\frac{7}{8}$

Substituting this back into the function, we get $f\left(\frac{7}{8} \right)=4\left(\frac{7}{8} \right)^2 -7\left(\frac{7}{8} \right)^2 -15=-\frac{289}{16}$

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1 year ago

A clothing store sells a customer 3 T-shirts and 4 pairs of shorts for $83.

ss7ja [257]

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3 years ago

The table below shows the average attendance of school events by the day of the week on which they are held. Average Attendance

natka813 [3]

Hello! :)

_____________ ☆ ☆_____________________

Answer:

407

Step-by-step explanation:

The answer is 407 because....

300/184 x 250

=407.60