<p>someone please help me some math problems that from BB..page464#19,
page462 #12, page587 #19 page 737 #15 , i know some of them were solved ,but i need a little more explantion, please be more specific...</p>
<p>page 464 #19
First, we know that the length of qr is 6pi, and since it corresponds to 30 degrees, we know that 6pi=(30/360)(3(pi)r). This is because out of the 360 degrees in a circle, 30 degrees in a circle has a length of 6pi. If you solve for r, which is the radius, the answer comes out to be 36. Plug it in the area formula: a=36^2pi which will give you an area of 1296pi. Then since they only want the 30 degree portion of it, and 30/360 is 1/6, multiply 1296pi by 1/6. The answer you get should be a. 108pi</p>
<p>Work:
QR= 6pi
Circumference= 2pir
6pi=(30/360)(2pir)
r=36
a=pir^2=36^2pi=1296pi
1296pi(30/360)= 108pi</p>
<p>page 462 #12
since y=5x-10 and (a,b) lies on the x-axis, then b is 0. This is because when on the x-axis, the y-value is 0. Plug 0 for y in the equation (0=5x-10) and solve, giving you d. 2.</p>
<p>Work:
0=5x-10
5x=10
x=2</p>
<p>page 587 #19
If you cross multiply the proportions, a. is the only one that is different from the rest.</p>
<p>work:
a. ac=bf
b. af=bc
c. af=bc
d. af=bc
e. af=bc</p>
<p>737 #15</p>
<p>You need to draw a cube. Since the volume is 8, each side is the cube root of 8 = 2. The shortest distance from the center to the base is a line parallel to the vertical sides but with half the length. 2/2 = 1, so A is the correct answer.</p>
<p>oh, i see , thanks a million…</p>