Hi

h= -16t^2+80t+48 = 0   (object hitting the ground)

 -16t^2+80t+48 = 0

 16t^2-80t-48 = 0

 t^2-5t-3 = 0



 ||Positive value only for unit measure

0r

 -16(t-5/2)^2 + 100 + 48 = 0

 -16(t-5/2)^2 + 148 = 0

     t = 5/2 ± sqrt(148/16)

     t = 5/2 ± sqrt(37)/2 

 

Hi

two cars pass on a straight highway while traveling in opposite directions. 

One car is traveling 6 miles per hour faster than the other car.

Speeds  and    

After 1.5 hours the two cars are 171 miles apart.

D = rt

  1.5x + 1.5(x+6) = 171   ||Solve for x and List both speeds

 

Hi

probability that exacly 4 boys in 10 births = 

Note: The probability of x successes in n trials is: 

P = nCx*  where p and q are the probabilities of success and failure respectively. 

In this case p & q are = 1/2 or .5   and n = 10

 

Hi

Use the Distributive Property and combine Like Terms



   3x + 3 = 7x - 14 - 3  ||Adding  -3x and 17 to both sides of the EQ

        20 = 4x

         5 = x

 

Hi

 

 

Hi

Assume you meant:  

2r - s = 10   Or  

rs - s^2 = 12

 |Multiplying thru by 2 so as all denominators = 1

   (s+10)s - 2s^2 = 24

    s^2 + 10s - 2s^2 = 24

      10s - s^2 = 24

     s^2 - 10s + 24 = 0

factoring

   (s-6)(s-4) = 0

    (s-6) = 0  ,  s = 6  and r = 8

  0r (s-4) = 0 ,  s = 4  and r = 7

 

Hi

P(x ≥ 1) = 1 - P(x= 0) = 1-.07 =.93

P(x ≤ 2) = .07+.68 = .75  Or    1 - .21 - .03 - .01 = .75

 

Hi

Chris and Gilbert drove a total of 522 miles in 8.2 hours. 

Chris drove the first part of the trip and averaged 65 miles per hour. 

Gilbert drove the remainder of the trip and averaged 55 miles per hour.

D = rt

    || solve for t, time Chris drove

 

Hi

Please repost, giving the realationship between line 1 and line 2

 

Hi

8(y+2)=2(3y+4)

 8y+16=6y+8   Yes.  Good work

8y + 16 -6y-16  = 6y + 8 - 6y - 16    ||Combining Like Terms(variable on one side,numbers on the other

    2y = -8

     y = -4

 

Hi

the idea is that You substitute the x-value in the function given

x	f(x) = 2x^3

-2	-16  = 

-1	-2

0	0

1	2

2	16

 

Hi

Re: TY, might consider,  "A random sample of 10 heights is obtained" is not

what the question is in reference to.

"Find the proportion of male college students whose height is greater than 72 inches" 

P(x > 72) = 1 - P( z ≤ (72-70)/6.4) = 1 - P(z≤ .3125) = 1 - .6227 = .3773 



μ = 70  ,  σ = 6.4

Find the proportion of male college students whose height is greater than 72 inches.

SAMPLE: 10 heights 

P( x > 72) = 1 -  P(= 1 -P(z=.9882) = 1-.8385 = .1615  

TI normalcdf(z)  gives the portion of the area under the standard normal curve to the LEFT of the z-value entered.

Important to Understand z -values as they relate to the Standard Normal curve:

Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.  

For ex: normalcdf(2) - normalcdf(-2) would give the portion of the area under the curve between those two z-values 

Note: z = 0 , 50% of the area under the curve is to the left and 50%  to the right

 

Hi

μ = 5.338  ,  σ = .068 

vending machine is configured to accept those coins with weights between 5.208 g and 5.468 g.

SAMPLE: 250 different coins

P(5.208 < x < 5.468) = P(  -   P(

find this difference and multiply times 250 (rounding UP to the nearest integer )

TI normalcdf(z)  gives the portion of the area under the standard normal curve to the LEFT of the z-value entered.

Actually can do in one step for between two z-values: normalcdf(smaller z, larger z)

Important to Understand z -values as they relate to the Standard Normal curve:

Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.  

For ex: normalcdf(2) - normalcdf(-2) would give the portion of the area under the curve between those two z-values 

Note: z = 0 , 50% of the area under the curve is to the left and 50%  to the right

 

Hi

taveling at the same speed..there is going to be NO 'catching-up' by Brenna

 

Hi

an exploration team of 2 women and 3 men is to be chosen from a candidate pool of 6 women and 7 men. 

how many different ways can this team of 5 be formed?  ways

 

Hi

Woods: 6 under par

Furyk: 3 under par

Daly: 1 over par

Couples: 6 over par

Woods beat Couples by 12 strokes

 

Hi

 60n = 30n + 400

 30n = 400

   n = 400/30 = 40/3  0r  

and

  

 

Hi

He spends £10 on a meal and then one-quarter of what he has left on a taxi home. 

He now has half of what the he started with.

Best to Set it Up Algebraically:

    |Multiplying thru by 4 so as all denominators = 1

    4x-40 - (x-10) = 2x

            x = £30, amount he started with

and...

£30 - £10  - £5 = £15

 

Hi

suppose a computer virus begins by infecting 8 computers in the first hour after it is released. 

each hour after that, each newly infected computer causes 8 more computers to become infected. 

the function y=8^x models this situation.make a table with integer values of x from 1 to 4

x	y = 8^x

1	8

2	64

3	512

4	4096

 

Hi

The value of a stock in dollars at the end of each month in 1992 varied according to the equation 

c(x) = 1/4x^2 - 2x + 6 = 1/4(x-4)^2 + 2 where x represents the number of months.

a)For how many months did the stock decrease? 4 mos

b)For how many months did the stock increase? 8mos

Might recommend Your downloading this FREE graph software

 www.padowan.dk 

 

Hi

Is y = 1/4x^0.5 a function?  yes, satisfies the vertical Line test.

Might recommend downloading the following FREE graph software

 www.padowan.dk 

 

Hi

what is the weight of a cuboidal block of ice of each edge 60cm in lenght

 if one cubic meter of ice weights 900 kilograms.

1m = 100cm, 60cm = .6m,  (.6)^3 = .216m^3, 

 

Hi

 

Hi



 

 

Hi

Standard Form of an Equation of an Hyperbola opening right and  left is:

   with C(h,k) and vertices 'a' units right and left of center,   2a the length of the transverse axis

Foci are  units right and left of center along y = k

25x2+50x-9y2-18y-209=0   || putting into Standard form

 25(x+1)^2 - 9(y+1)^2 - 25 + 9 - 209 = 0

 25(x+1)^2 - 9(y+1)^2 = 225



center:  C(-1,1)

foci:  F(-1+,1)  and F(-1-,1)

 

Hi

A sample of 4 different calculators is randomly selected from a group

containing 16 that are defective and 30 that have no defects:   in all

P(at least 1 defective) = 1 -P(none defective) = 1 - 

 

Hi

If you are dealt two cards successively (with replacement of the first) from a standard deck of 52 playing cards

P(H then D) = 

 

Hi

 = 1266.7m/min

 

Hi

  7lb 8 oz

- 0lb 8.6 oz



 6lb 24.0 oz    || Borrowing 1 lb 0r 16oz, so as able to subtract ounces

- 0lb  8.6 oz   = 6lb 15.4 oz lighter

 

Hi, Here is one as an example that was just previously posted

x2+12x-5=0

x2+12x = 5

4x2+48x = 20

4x2+48x+144 = 164 

 = ± sqrt(164)

      2x + 12 = 2sqrt(41)

           x = -6 +sqrt(41)

      2x + 12 = -2sqrt(41)

            x = -6 -sqrt(41)



Checking using 'Completing the Square'

(x+6)^2 = 5 + 36

   x+6 =  ±sqrt(41)

    x = -6 ±sqrt(41)