Mathematics - 30 October 2007

ABCD is a rectangle in which the co-ordinates of A and C are (0,4) and (11,2) respectively. The gradient of ab is -5.
1)Find the equations of ab and bc
2)Show that the co-ordinates of b are (1,-1)
3)Find the area of rectangle ABCD

The points A(2,5) and B(-4,13) lie in the opposite ends of a diameter of a circle with centre C.
a) Find the radius and centre of the circle
b)Find the equation of the circle in the form x^2+y^2 +px+qy+c=0
c)Find the equation of the normal at a and the tangent of b

If you can do ANY of these please do, and put how you do it. Sorry-but i got stuck!!!

2007-10-30 23:57:56 · 1 answers · asked by xMwahahahahahahax 3

Evaluate the following expression when z = 12: (z + 8)/4

A. 5
B. 11
C. 14
D. 20

2007-10-30 23:10:49 · 4 answers · asked by Anonymous

Solve for x: 2x + 3 = 7.

A. 4
B. 2
C. 5
D. 8

2007-10-30 22:59:20 · 12 answers · asked by Anonymous

Solve for h: 21 = 9 + 3h.

A. 9
B. 4
C. 10
D. 36

2007-10-30 22:58:49 · 16 answers · asked by Anonymous

A. 25
B. 15
C. 4
D. 100

2007-10-30 22:46:49 · 9 answers · asked by Anonymous

another math prob!!!

2007-10-30 22:40:07 · 12 answers · asked by Anonymous

You’re asked to convert a large value (given in centimeters) to its equivalent value in miles. You already know that 30.48 centimeters equals 1 foot. You’ll also need to know that

A. 16 ounces = 1 pound. C. 3 feet = 1 yard.
B. 2.54 centimeters = 1 inch. D. 5280 feet = 1 mile.

2007-10-30 21:49:22 · 9 answers · asked by Saran K 2

Find all the zeros of the following:

g(x) = 2x^5 - x^4 - 5x^3 + 10x^2 - 2x - 4

2007-10-30 21:27:32 · 3 answers · asked by beeboroachgoingon197 1

L1 : (x+3)/1 = (y-7)/4 = (z-2)/1

L2 : a line goes through (0,2,1) and (-4,4,1)

i found the parametric equations

L1: x = -3 - t, y = 7 + 4t, z = 2 + t
L2: x = -4s, y = 2 + 2s, z = 1

i set L1 = L2 but i can't find any s and t values that satisfy.

I used t = -1 initially and plugged them into L1's parametric equation and got the answer in the back (-2,3,1), but if i solve for s which I got, was s = 2, i get (-8,6,1).

HELP!!!

2007-10-30 21:05:07 · 2 answers · asked by fye 1

i am analysing my data from drugs treatment using animal model. any idea to estimate data from a standard curve, for example identifying LD50 value. I mean any software for this function (free software?))?

2007-10-30 20:50:19 · 4 answers · asked by june81 2

Please help me with this Maths question!!!!
"OABC is a regular tetrahedron. M,N,O and P are the midpoints of OA,OB,AC,BC respectively. Let OA=a, OB=b, OC=c. Using vector methods, prove that MQ is perpendicular to NP"

Thanks a lot in advance.

2007-10-30 20:47:34 · 1 answers · asked by coucou_bambie 2

2007-10-30 20:38:03 · 2 answers · asked by generalche22 3

what is the area formula for square?

2007-10-30 19:58:09 · 8 answers · asked by rachel 1

If production line A can produce 12.5 units in an hour and production line B can produce
15.25 units in an hour, how long will the production line A have to work to produce the
same amount of units as line B?
the answer is 1.22 hours..
If you can show me the work ,and how you arrived at the answer ,you would help me out tremendously . It is a sample question that will be on an exam for employment that I am taking on Thursday ..thanks in advance..and 10 points for the 1st correct answerer.

2007-10-30 19:53:42 · 13 answers · asked by Dfirefox 6

∫4cos7xcos3x dx

2007-10-30 19:52:56 · 4 answers · asked by mikemallow 1

I have this problem on my math homework. Unfortunately, I put it off until the last minute and I don't remember how to do it.
We've been rewriting exponential functions and solving them. How do I do this?

100(1.04)^2t=300

And can you also explain the math behind what I'm doing for other problems.

Thank you!!

2007-10-30 19:45:42 · 3 answers · asked by mew1033 2

2007-10-30 19:12:45 · 4 answers · asked by Anonymous

Assume that it is known that the adjoint of a matrix A is

adj A=
–6 –4 -8
-4 -4 -6
6 3 8

Then A itself is either ___ ___ ___
___ ___ ___
___ ___ ___
or
___ ____ ___
___ ____ ___
___ ____ ___

2007-10-30 19:05:19 · 2 answers · asked by Anonymous

If lnx+ln(x–4)=ln2x
then x=?

2007-10-30 19:01:59 · 3 answers · asked by Anonymous

Two points equidistant from the sides of an angle lie on the bisector. Is this always, sometimes, or never true?

I believe its sometimes because two points can be equidistant but be outside of the angle or equidistant and not touching the midpoint in the center of the angle. Explain your answer please and thank you.

2007-10-30 19:00:04 · 3 answers · asked by Chead 1

2007-10-30 18:59:33 · 7 answers · asked by johnny b 2

Assume that A and B are 3x3 matrices with det A= –4 and det B= –5 . Then
det((A^–1)–3adj(A))

2007-10-30 18:39:04 · 1 answers · asked by Anonymous

Suppose that a volcano is erupting and readings of the rate r(t) at which solid materials are spwed into the atmosphere are given in table 1. The time measured in seconds and the units for r(t) are tonnes (metric tons) per second.

r(0) = 2
r(1) = 10
r(2) = 24
r(3) = 36
r(4) = 46
t(5) = 54
r(6) = 60

Give upper and lower estimates for the quantity Q(6) of erupted materials after 6 seconds. Justify in complete sentences how you know you have upper and lower estimates

And use midpoint rule to estimate Q(6)

This is what I did:

I know that ∫r(t)dt = Q(t)
that must mean Q(6) is the area under the curve of r(t) from 0 to 6. So how do I get the upper bound and lower bound?

For the midpoint rule this is what i did
Q(6) = ∫r(t)dt from 0 to 6 = [(2+10)+(10+24)+(24+36)+(36+46)+(46+54)+... = 201 tonnes

??????????

2007-10-30 18:18:55 · 2 answers · asked by Anonymous

lets say i have a group of number... 0,0,1,1,2,3
how can i find all possible 4 digit group from those number?? without the 4 digit group having a duplicate group... meaning that if i have 1 group consisting 0011, i dun need 0101, or 1100 or anything that comes out from this 4 digit together...
by the way... are there any program that is capable to do that??

2007-10-30 18:14:13 · 1 answers · asked by DéJà Vu 1

I am confused, are you supposed to divide by 4 on both sides? or subtract 15 from both sides?

2007-10-30 18:08:07 · 6 answers · asked by Danyizzle 4

2007-10-30 18:06:46 · 11 answers · asked by Anonymous

2007-10-30 18:05:32 · 9 answers · asked by Anonymous

2007-10-30 17:57:50 · 11 answers · asked by Anonymous

2007-10-30 17:44:38 · 3 answers · asked by Anonymous

Find the common solution for each system of equations using elimination and/or substitution.

1) x + y = 20 x - y = 10
2) x + y = 8 x - y = -2
3) x + y = 5 x - y = -3
4) x - y = 4 3x + 2y = 7
5) 5x + 5y = -5 3x - y = -7
6) 4x - y = 1 2x + y = 17
7) 2x - y = 4 2x + 4y = 4
8) -x + 3y = 14 x + 22 = 5y
9) 8x - 6y = 2 2x + 3y = 2
10) 2x - 5y = 10 3x - 2y = -7

2007-10-30 17:39:09 · 3 answers · asked by erikjjjacob 1