Math Worksheets

Archive for October, 2008

Question: how to do surface area?

i was sick for a long time and i need someone to walk me through surface area! i have like 10 worksheets to do of itt:[

well i need the surface area of a cylinder and rectangular prism, and triangular prism!
thanks!

(i'm in seventh grade pre-algebra)

Answer: Add up the area of all the sides of the figure.
Do you know how to use formulas? :]

Cylinder:
2(pi)rh + 2(pi)r(squared)

Rectanglular Prism:
Just find the area of all the faces of the prism and add them up

Triangular Prism:
Find the area of the two triangular sides and then add it do the rectangular sides.

Basically surface area is just measuring the outside area of a figure.

Interactive Math – YourTeacher.com – 1000+ Online Math Lessons

What are the Prime factors of 136?

Dividing 136 by the smallest prime number, 2.

136 ÷ 2 = 68

136 = 2 x 68

Dividing 68 by the smallest prime number, 2.

68 ÷ 2 = 34

136 = 2 x 2 x 34

Dividing 34 by the smallest prime number, 2.

34 ÷ 2 = 17

136 = 2 x 2 x 2 x 17

Dividing 17 by the smallest prime number, 2.

17 ÷ 2 = 8.5, not an integer (whole number so move on to the next prime number)

Once you have found a prime factor, keep dividing the remainder by the same prime factor until the remainder is no longer a whole number (an integer). When that happens, move on to the next prime number.

Question: Need AP Calculus Help!!!!?

I have a worksheet due in math and I can’t do a few of them. Can anyone please help?

1) The Kertz Leasing Company leases fleets of new cars to large corporations. The rental fee is $2000 per car per year. However, for contracts with a fleet size of more than 10 cars, the rental fee per car is discounted by 1% for each car in the contract, up to a maximum fleet of 75 cars. How many cars leased to a single corporation in one year will produce (A) maximum revenue and (B) maximum profit if each car depreciates in value $1000 per year.

and….

2) A point P is taken on the curve y=x^3. The tangent at P meets the curve again at Q. Prove that the slope of the curve at Q is four times the slope at P.

Answer: 2) Let (p, p^3) and (q, q^3) be the two points on the curve. Since dy/dx = 3x^2, the tangent at point P has a slope of 3p^2. Likewise, the slope of the tangent at Q is 3q^2.

The slope of the line passing through (p, p^3) and (q, q^3) is
(p^3 – q^3) / (p-q), which is
(p-q)(p^2 + pq + q^2) / (p-q) =
p^2 + pq + q^2

This is equal to the slope of the tangent at point P, since it’s the same line. So
p^2 + pq + q^2 = 3p^2
-2p^2 + pq + q^2 = 0
2p^2 – pq – q^2 = 0
(2p + q)(p – q) = 0
So either p-q=0 or 2p+q = 0, meaning either p=q or p = (-1/2)q. We know p and q are not the same, because that would Mean points P and Q are the same. So p = (-1/2)q

The slope of the tangent at Q is 3q^2. The slope of the line at p is 3p^2, which is 3(q^2 / 4). This shows that the slope at Q is four times as big as the slope at P.

Finding the Slope Given 2 Points