Answer:
-3
Step-by-step explanation:
2a - 6 = 4a
subtract 2a giving you -6 = 2a
divide by 2 from both sides so that a will be by itself
giving you -6 ÷ 2 = a
-6 ÷ 2 = -3
so a = -3
To solve this, write a proportion of Pounds to Cost:
Pounds: 3 x
Cost: 25.50 42.50
Cross multiply 3 and 42.50, this gives you 127.5
Then, divide by 25.5
This gives you 5.
You can buy 5 pounds with $42.50
Answer:
7.4. I BELIEVE...sorry if i did it wrong
Step-by-step explanation:
1 2/3 + 1 2/3 = 3.33333333
2 + 2 = 4
3.333333 + 4 = 7.333333
7.333333 rounded would be 7.4
Answer:
cubic units
Step-by-step explanation:
We are to find the volume of the solid of revolution formed by rotating about the x--axis the region bounded by the given curves.
f(x)=2x+1, y=0, x=0, x=4.
The picture is given as shaded region.
This is rotated about x axis
Limits for x are already given as 0 and 4
f(x) is a straight line
The solid formed would be a cone
Volume = ![\pi \int\limits^a_b {(2x+1)^2} \, dx \\= \pi \int\limits^4_0 {(4x^2+4x+1)} \, dx \\=\pi [\frac{4x^3}{3} +2x^2+x]^5_0\\\\=\pi[\frac{4*4^3}{3}+2*4^2+4-0]\\=\frac{364\pi}{3}](https://tex.z-dn.net/?f=%5Cpi%20%5Cint%5Climits%5Ea_b%20%7B%282x%2B1%29%5E2%7D%20%5C%2C%20dx%20%5C%5C%3D%20%5Cpi%20%5Cint%5Climits%5E4_0%20%7B%284x%5E2%2B4x%2B1%29%7D%20%5C%2C%20dx%20%5C%5C%3D%5Cpi%20%5B%5Cfrac%7B4x%5E3%7D%7B3%7D%20%2B2x%5E2%2Bx%5D%5E5_0%5C%5C%5C%5C%3D%5Cpi%5B%5Cfrac%7B4%2A4%5E3%7D%7B3%7D%2B2%2A4%5E2%2B4-0%5D%5C%5C%3D%5Cfrac%7B364%5Cpi%7D%7B3%7D)
