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Polynomials-and-rational-expressions/324737: Simplify 1/z-1 - 1/z+1 1 solutions Answer 232452 by rfer(12729)   on 2010-07-22 13:23:09 (Show Source): You can put this solution on YOUR website! looks like 0

Exponents/324658: I am new at this so here is my problem.-2(5n+5)+6(n-8). I don't understand the order of operations or how to solve. 1 solutions Answer 232444 by rfer(12729)   on 2010-07-22 12:35:42 (Show Source): You can put this solution on YOUR website! remember please excuse my dear aunt sally () x^2 * / + - -2(5n+5)+6(n-8) -10n-10+6n-48 -4n-58

Rectangles/324677: he perimeter of a rectangle is 66cm if the length is twice the width,what are the dimension of the rectangle? 1 solutions Answer 232442 by rfer(12729)   on 2010-07-22 12:29:13 (Show Source): You can put this solution on YOUR website! 2w+2(2w)=66 6w=66 w=11 cm 2w=22 cm

percentage/324712: What is the value of the expression 2x2+3xy-when x=2 and y= -4 1 solutions Answer 232441 by rfer(12729)   on 2010-07-22 12:26:11 (Show Source): You can put this solution on YOUR website! 2*2^2+3*2*-4 8-24=-16

Numeric_Fractions/324592: Simplify (1/4)(-2/7)(5/8)(7/6) 1 solutions Answer 232346 by rfer(12729)   on 2010-07-22 01:19:50 (Show Source): You can put this solution on YOUR website! -2/28*5/8=-10/224 -10/224*7/6=-70/1344=-5/96

Equations/324591: solve 1/3=n/ 4 1/7 1 solutions Answer 232345 by rfer(12729)   on 2010-07-22 01:17:29 (Show Source): You can put this solution on YOUR website! n=1/3*4 1/7 n=1/3*29/7 n=29/21 n=1 8/21

Angles/324497: give the measure of the angle that is complementary to an angle the measures 71 degrees 1 solutions Answer 232256 by rfer(12729)   on 2010-07-21 20:17:03 (Show Source): You can put this solution on YOUR website! 90-71=19 degrees

Polynomials-and-rational-expressions/324467: is 6abcxyz a trinomial a binomial or a monomial? 1 solutions Answer 232231 by rfer(12729)   on 2010-07-21 16:49:48 (Show Source): You can put this solution on YOUR website! monomial, it has just one term

Volume/324457: could you please tell me how many litres would fill a container measuring 9ft x 8ft x 2.5ft 1 solutions Answer 232230 by rfer(12729)   on 2010-07-21 16:47:27 (Show Source): You can put this solution on YOUR website! 9*8*2.5=180 cu ft 180*28.32=5097.6 liters

Linear-equations/324342: determine the present value you must invest to have a future value of $8,500 when the simple interest rate is 7% for 3 years 1 solutions Answer 232226 by rfer(12729)   on 2010-07-21 16:25:15 (Show Source): You can put this solution on YOUR website! A=P(1+r)^n P=A/((1+r)^n) P=8500/((1.07)^3) P=8500/1.225 P=6938.78

Complex_Numbers/324413: -(4w-y)-(w-5y) 1 solutions Answer 232221 by rfer(12729)   on 2010-07-21 16:17:43 (Show Source): You can put this solution on YOUR website! -4w+y-w+5y -5w+6y

Distributive-associative-commutative-properties/324452: how do you solve a commutative prop. of addition 1 solutions Answer 232220 by rfer(12729)   on 2010-07-21 16:15:25 (Show Source): You can put this solution on YOUR website! all communitive properties do is let you add in any order. 3+4=7 4+3=7

Linear-equations/324429: Solve the following equations for the unknown. 6.2(x - 15.1) = 9.3(-x - 3.2) 1 solutions Answer 232219 by rfer(12729)   on 2010-07-21 16:12:33 (Show Source): You can put this solution on YOUR website! 6.2x-93.62=-9.3x-29.76 -3.1x=63.86 x=-20.6

Equations/324434: On Sunday, a local hamburger shop sold a combined total of 520 hamburgers and cheeseburgers. The number of cheeseburgers sold was three times the number of hamburgers sold. How many hamburgers were sold on Sunday? 1 solutions Answer 232218 by rfer(12729)   on 2010-07-21 16:02:13 (Show Source): You can put this solution on YOUR website! 520/4=130 hb 130*3=390 cb

Rectangles/324448: The width of a rectangle is 3 less than the length. If the perimeter is 50 meters, find the length and width.. 1 solutions Answer 232217 by rfer(12729)   on 2010-07-21 15:58:52 (Show Source): You can put this solution on YOUR website! 2(x-3)+2x=50 2x-6+2x=50 4x=56 x=14 x-3=11

Numbers_Word_Problems/324234: the sume of two numbers is twenty five. the smaller number is equal to five less than the larger number. find both numbers 1 solutions Answer 232055 by rfer(12729)   on 2010-07-20 20:35:51 (Show Source): You can put this solution on YOUR website! x+x-5=25 2x=30 x=15 x-5=10

Volume/324235: The dimensions of the interior of an upright freezer are height 46 in., width 25 in., and depth 25 inches. Determine the volume of the freezer in inches cubed 1 solutions Answer 232054 by rfer(12729)   on 2010-07-20 20:34:25 (Show Source): You can put this solution on YOUR website! 46*25*25=28,750 cu in

Travel_Word_Problems/324154: two cars leave form the same point traveling in opposite directions. One travels 35 miles per hour and the other 50 mph. How many hours wil it take them to be 170 miles apart 1 solutions Answer 232014 by rfer(12729)   on 2010-07-20 18:30:17 (Show Source): You can put this solution on YOUR website! 170/85=2 hrs

Geometry_Word_Problems/324155: All of the rooms in a building are rectangular, with nine-foot ceilings. One room is 10 feet wide by 14 feet long. What is the combined area of the four walls, including doors and windows? 1 solutions Answer 232013 by rfer(12729)   on 2010-07-20 18:28:52 (Show Source): You can put this solution on YOUR website! A=10*14*9 A=1260 sq ft

Geometry_Word_Problems/324170: perimeter of a rectangle. 10ft. long by 6ft.8in. wide? 1 solutions Answer 232012 by rfer(12729)   on 2010-07-20 18:26:37 (Show Source): You can put this solution on YOUR website! p=2*10+2*6 2/3 p=20+13 1/3 p=33ft 4 in

Numeric_Fractions/324175: what is the average (arithmetic mean) of 8,7,7,5,3,2, and 2? 1 solutions Answer 232011 by rfer(12729)   on 2010-07-20 18:21:50 (Show Source): You can put this solution on YOUR website! 34/7=4.86

Geometry_Word_Problems/324017: A rectangle has a length of 80in and a width of 34in. What is it's perimeter? 1 solutions Answer 231910 by rfer(12729)   on 2010-07-20 13:37:11 (Show Source): You can put this solution on YOUR website! p=2L+2w p=2*80+2*34 p=160+68 p=236 in

Percentage-and-ratio-word-problems/324041: 7 1/2 percent of 8 percent is (A) 0.06% (B) 0.6% (C) 6% (D) 60% (E) 600% 1 solutions Answer 231906 by rfer(12729)   on 2010-07-20 13:33:03 (Show Source): You can put this solution on YOUR website! .08*.075=0.006=0.6%

Mixture_Word_Problems/324065: a chemical solution contains 1% salt. How much salt is in 2.5 ml of solution? Round your answer to the three decimal places. 1 solutions Answer 231905 by rfer(12729)   on 2010-07-20 13:29:33 (Show Source): You can put this solution on YOUR website! 2.5*0.01=0.025=2.5%

Money_Word_Problems/324060: I have two questions: 1) $6,000 is invested in each of two accounts, both paying 7% annual interest. In the first account, interest compounds quarterly, and in the second account, interest compounds daily. Find the difference between the accounts after 21 years. (Give your answer correct to the nearest cent.) 2) An initial deposit of $25,000 grows at an annual rate of 9% for 15 years. Compare the final balances resulting from annual compounding and continuous compounding. (Give your answers correct to the nearest cent.) a) with Annual Compounding b) with continuous compounding Can you please help me work through both of these? Thank you, jerry jerry@san.rr.com 1 solutions Answer 231904 by rfer(12729)   on 2010-07-20 13:27:55 (Show Source): You can put this solution on YOUR website! A=P(1+r/n)^nt A=6000(1+0.07/4)^4*21 A=6000(1.0175)^84 A=6000*4.29429 A=25,765.72 ------------------ A=6000(1+0.07/365)^365*21 A=6000(1.000191781)^7665 A=6000*4.348628 A=26,091.77 -------------------- 26091.77-25765.72=326.05 difference ------------------------ For number two A use A=P(1+r)^15 For two B use A=Pe^rt A=P*2.7183^.09*15 ---------------- Good luck

Miscellaneous_Word_Problems/323796: The Everton College store paid $1564, for an order of 42 calculators. The store paid $10 for each scientific calculator. The others, all graphing calculators, cost the store $54 each. How many of each type of calculators was ordered? 1 solutions Answer 231737 by rfer(12729)   on 2010-07-19 18:35:32 (Show Source): You can put this solution on YOUR website! s+g=42 s=42-g 10s+54g=1564 10(42-g)+54g=1564 420-10g+54g=1564 44g=1144 g=26 graphing 42-26=16 scientific

Miscellaneous_Word_Problems/323643: A single card is drawn from a standard 52-deck of cards with four suits; 13 cards per suit. If each siot has three face cards, how many ways could the drawn card be either a heart of any kind or a face card? 1 solutions Answer 231680 by rfer(12729)   on 2010-07-19 16:23:00 (Show Source): You can put this solution on YOUR website! 3*3*3*13=351

Equations/323747: 3(-n – 1) = -16n + 49 1 solutions Answer 231678 by rfer(12729)   on 2010-07-19 16:15:36 (Show Source): You can put this solution on YOUR website! -3n-3=-16n+49 13n=52 n=4

Money_Word_Problems/323651: Mary just deposited $33,000 in an account paying 7% interest. She plans to leave the money in this account for eight years. How much will she have in the account at the end of the seventh year? 1 solutions Answer 231677 by rfer(12729)   on 2010-07-19 16:14:32 (Show Source): You can put this solution on YOUR website! I assume annual compounding? A=33000(1+.07)^7 A=33000*1.61 A=$53,130.00

Numbers_Word_Problems/323688: find two numbers whose sum is 55. the larger number is 4 more than twice the smaller 1 solutions Answer 231676 by rfer(12729)   on 2010-07-19 16:09:15 (Show Source): You can put this solution on YOUR website! x+2x+4=55 3x=51 x=17 2x+4=38

Square-cubic-other-roots/323707: to slove for x. 1 solutions Answer 231675 by rfer(12729)   on 2010-07-19 16:06:42 (Show Source): You can put this solution on YOUR website! 7/3.14=x^2 2.2293=x^2 x=1.493