Hi,

 

Hi,

x^2+8x=20

x^2+8x + 16 =20 +16

(x + 4)(x+4) = 36

 (x+4)^2 = 36

 

Hi,

of the 500 graphing calculators , 10 were defective.  non-defective

math class received 30 calculators

P(all non-def) = 

 

Hi,

The cost of 6 bedspreads and 8 pillows is $448.12. 

Three bedspreads and 10 pillows cost $323.00. 

Find the cost of each bedspread and each pillow.

Translate into two equations: 

 6x + 8y = 448.12

 3x + 10y = 323.00  ||Multiply 2nd Eq by -2 and add to 1st EQ to eliminate x

     -12y = -197.88

        y = $98.94

 

Hi,

if the reserve rate is 9%and a bank recieves a deposit of 8000 how much of the 8000 is the bank free to lend

 

Hi,

a boat takes 3 hours to travel 30 km down a river, 

then 5 hours to return. how fast is the river flowing?

Note:  D/t = r

 r + c = 10  

 r - c = 6   

 2r = 16

  r = 8   and c = 2kmph, how fast the river is flowing

 

Hi,

The longer leg of a given right triangle is 7ft greater in length than the shorter leg of the triangle. 

The hypotenuse is 2ft greater in length than the longer leg of the triangle.

Using the Pythagorean Theorem

  a^2 + b^2 = c^2

 a^2 + (a+7)^2 = (a+9)^2

 a^2 + a^2 + 14a + 49 = a^2 + 18a + 81

    a^2 - 4a - 32 = 0

factoring

 (a -8)(a + 4) = 0

 (a + 4) = 0 ,  a = -4  ||disregard negative solution for unit measure

0r (a - 8)= 0 , a = 8ft,  b = 15ft,  c = 17ft

and...



 

 

Hi,

Re TY, as below(blue line), draw a vertical line up and down at x = -3

 x = -3  is a vertical Line.

Domain is x = -3

Range is all real numbers

 

Hi,

The sum of three numbers, ,&is 137.

The second number is 4 more than two times the first number. 

The third number is 5 less than three times the first number.

Translate into an equation: 

  x +   y    +  z     = 137

  x +  +  = 137

      6x = 138

       x = 23

three numbers are:  23, 50, 64

and...

 

Hi,

 ⇒  ⇒ , x =  



⇒ ⇒  

 

Hi,

Note: one 'solves' equations... expressions are 'simplified' if possible

 

Hi,

alex drove 84 miles on 6.5 gallons of gas 

how many gallons would he need to travel 126 miles?

   ||| Cross Multiply to solve for x

 

Hi,

90 calories in 3/4 cup how many carlories are in 9 cups?

   | Cross Multiplying to solve

   x = 810/.75 = 1080 calories

 

Hi,



   (3x)^2 = 81

     9x^2 = 81

      x^2 = 9

       x = 3   (tossing out -3 as being an extraneous solution)

 

Hi,

scale of a park is 1 inch = 20 feet,measuremaent on the map of 6 inches 

stands for how much distance is the actual park

  ||| Cross Multiply to find x = 120ft

 

Hi,

A car averages 400 km per tankful of gasoline.(2 tankfuls, 800km)

At 70 kilometers per hour, about how many hours can you drive on 2 tankfuls?

  = ~11.4hrs

 

Hi,Previously Posted

Note:  t = D/r



   3600(v+25) - 3600(v-25) = v^2 - 625

         7200*25 +625 = v^2

               425mph = v

and..

 

Hi,

Note:  t = D/r



   3600(v+25) - 3600(v-25) = v^2 - 625

         7200*25 +625 = v^2

               425mph = v

and..

 

Hi,

μ = 100 ,  σ = 20 

P(x>105) = 1 - P(x ≤ 105) = 1 - P()

                          = 1 - P(z ≤ 5/2)=.0062

 

Hi,

The fraction 7/12 is found between which pair of fractions on the number line.

  7/12 > 1/2  

d) 8/16 and 17/24   as this goes from 1/2 to over 2/3

 

Hi,

Using the standard slope-intercept form for an equation of a line y = mx + b

  where m is the slope and b the y-intercept.

m:12, y-intercept:4/5

 y = 12x + 4/5  (0,4/5) and (-1/15,0) the intercepts

Plot Pts and connect with the Line

 

Hi,

vertex(2,-8) and line of symmetry x = 2 and intercepts shown

Range:  F(x) ≥ -8, Domain:  x all real numbers

f Increaseing ( 2,∞ )  and f is decreasing(−∞,2)

 F(x) = x^2 - 4x- 4 = x^2 - 4x + 4 - 4 - 4 = (x-2)^2 - 8

 

Hi,

A school code consists of two letters followed by 3 digits.  

The first letter must be one of  letters: K, F, S, T, U, or I. 

 How many codes meet this description? 

How many codes meet the additional restrictions: no repeated letter, and no digit can be the 0 digit?

 

Hi,

-12x + 4y = 12 

        y = 3x + 3

 

Hi,

Re TY

'combining' the d terms requires -2d to be added to both sides

2d+6=3(d-3)

 2d + 6 = 3d - 9    ||Adding 9 and -2d to both sides of the EQ

     15 = d

and..

 

Hi,

 

Hi,



 width is two less than three times the length, what is the equation?

  P= 2L + 2W = 36"

      L + W = 18"    

     x + (3x-2) = 18" , x = 5" , the length and width is  13"

 

Hi, Previously Posted

The price of a radio at Store A is 29/30 the price at Store B.



     = $156

 

Hi,

The price of a radio at Store A is 29/30 the price at Store B.



     = $156

 

Hi,

 line with an 'undefined' slope is a vertical Line

passing thu (-9/2,4)   x = -9/2

 

Hi,

If I am understanding correctly

 9 + 4 = 9 + 1 + 3 = 10 + 3 = 13