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Recent problems solved by 'checkley71'

checkley71 answered: 8399 problems
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expressions/125062: I am trying to write this without parentheses 1 solutions Answer 91675 by checkley71(8403)   on 2008-02-05 15:16:32 (Show Source): You can put this solution on YOUR website! [U^2/-3V]^2=U^2/9V^2 ANSWER. [((-3)Y^2/Z^3)^2=9Y^4/Z^6 ANSWER.

Rectangles/125063: Find the range for the measure of the third side of a triangle with the given two sides 31 and 4. 31 > x > 4 35 > x > 4 35 > x > 27 35 > x > 31 Couldnt it be B or C. Say it was C and the third side is 28 or 34. 31+4 is more than 28 and 34. Say the third side was 31 28+4 is more than 31. Say the answer was D and the third side was 32 or 34. 31+4 ir more than 32 and 34. So i am not sure 1 solutions Answer 91674 by checkley71(8403)   on 2008-02-05 15:11:07 (Show Source): You can put this solution on YOUR website! THE MINIMUM LENGTH IS 31-4=27 THE MAXIMUM LENGTH IS 31+4=35 THUS THE INEQUALITY IS: 35 > X > 27.

Probability-and-statistics/125013: This question is from textbook Algebra 2 Twice the number of pansies exceeded 4 times the number of daises by 8. Also, 7 times the number of daisies was 4 less than 3 times the number of pansies. How many of each were there? 1 solutions Answer 91643 by checkley71(8403)   on 2008-02-05 11:26:45 (Show Source): You can put this solution on YOUR website! 2P=4D+8 OR P=2D+4 7D=3P-4 NOW SUBSTITUTE (2D+4) FOR P IN THIS EQUATION. 7D=3(2D+4)-4 7D=6D+12+4 7D-6D=16 D=16 ANSWER FOR THE NUMBER OF DAISIES. P=2*16+4 P=32+4 P=36 ANSWER FOR THE NUMBER OF PANSIES. PROOF 7*16=3*36-4 112=108+4 112=112

Sequences-and-series/125006: find two consecutive numbers whose product is 72 1 solutions Answer 91641 by checkley71(8403)   on 2008-02-05 11:17:35 (Show Source): You can put this solution on YOUR website! X(X+1)=72 X^2+X-72=0 (X+9)(X-8)=0 X+9=0 X=-9 ANSWER. X-8=0 X=8 ANSWER.

Equations/125001: In excersise 33-41,Use the given information to find the given amount. 40. Food bill: $20 Sales tax: 5% Any help with this equation would be Greatly appreciated. 1 solutions Answer 91635 by checkley71(8403)   on 2008-02-05 10:16:53 (Show Source): You can put this solution on YOUR website! 20+.05*20=20+1=$21 THE FINAL PRICE WITH TAX.

Percentage-and-ratio-word-problems/125004: The sales price of a car is $12,590, which is 20% off the original price. What is the original price? This just for practice. I wonder how they get $15737.90 $14,310.40 $14,990.90 $15,290.70 $15,737.50 $16,935.80 1 solutions Answer 91634 by checkley71(8403)   on 2008-02-05 10:12:44 (Show Source): You can put this solution on YOUR website! If you want to find a reduction of 20% and you don't have the original number, then you need to assign the original price an unknown(x)and subtract 20% from x. Thus we have the following equation. -------------------------------------------------------------------- (X-.2X)=12,590 SALE PRICE MINUS 20% OF THIS PRICE EQUALS $12,590. .8X=12,590 X=12,590/.8 X=$15,737.50 WAS THE ORIGINAL PRICE.

Equations/125003: Use the given information to find the given amount. You want to order a new computer. The manufacturer is offering a dicount of 12% off the original price of the computer. With the discount $924.What is the original price of the computer? Any help with this equation would be Greatly appreciated. 1 solutions Answer 91633 by checkley71(8403)   on 2008-02-05 10:08:23 (Show Source): You can put this solution on YOUR website! X-.12X=924 .88X=924 X=924/.88 X=$1,050 IS THE ORIGINAL PRICE BEFORE THE 20% DISCOUNT.

Equations/125000: In excersise 33-41,Use the given information to find the given amount. 39. Original Price: $15 Discount Percent:20% Any help with this equation would be Greatly appreciated. 1 solutions Answer 91632 by checkley71(8403)   on 2008-02-05 10:05:56 (Show Source): You can put this solution on YOUR website! 15-.2*15=15-3=$12 ANSWER FOR THE REDUCED PRICE.

Equations/124998: In excersise 33-41,Use the given information to find the given amount. 38. Wholesale price: $88 Markup Percent: 50% Any help with this equation would be Greatly appreciated. 1 solutions Answer 91631 by checkley71(8403)   on 2008-02-05 10:03:58 (Show Source): You can put this solution on YOUR website! 88+.5*88=88+44=$132 ANSWER FOR THE FINAL PRICE.

Equations/125002: In excersise 33-41,Use the given information to find the given amount. 41. Original price: $200 Sales tax:6% Any help with this equation would be Greatly appreciated. 1 solutions Answer 91630 by checkley71(8403)   on 2008-02-05 10:01:23 (Show Source): You can put this solution on YOUR website! 200+200*.06=200+12=$212 IS THE TOTAL FOR THE FINAL PRICE.

Quadratic_Equations/124999: Jane invested some amount at the rate of 12% simple interest and some other amount at 10% simple interest. She received yearly interest of $130. Randy also invested, and received $4 more as interest. How much amount did each of them invest at differen rates? 1 solutions Answer 91629 by checkley71(8403)   on 2008-02-05 09:59:11 (Show Source): You can put this solution on YOUR website! I apologize. Randy also invested in the same scheme, but he interchanged the amounts invested, and received $4 more as interest. How much amount did each of them invest at different rates? .12X+.10Y=130 THE FORMULA FOR JANE'S INVESTMENT. .10X+.12Y=134 THE FORMULA FOR RANDY'S INVESTMENT. MULTIPLY JANE'S FORMULA BY -10 & RANDY'S BY 12 THEN ADD THEM. -1.2X-1Y=-1300 1.2X+1.44Y=1608 ------------------------------ .44Y=308 Y=308/.44 Y=$700 INVESTED BY JANE @ 10% & BY RANDY @ 12%. ANSWER. .12X+.10*700=130 .12X+70=130 .12X=130-70 .12X=60 X=60/.12 X=$500 INVESTED BY JANE @ 12% & BY RANDY @ 10%. ANSWER. PROOF: .10*500+.12*700=134 50+84=134 134=134

Equations/124997: Each year,your school organizes a carnival to raise money for a class trip. This year, a total of 1026 people attended the carnival. By what percent did the attendance increase from last year to this year? Ive been having trouble trying to convert this problem any with this equation would be Greatly appreciated.Thanks 1 solutions Answer 91628 by checkley71(8403)   on 2008-02-05 09:53:55 (Show Source): You can put this solution on YOUR website! 1026/950=1.08 or 8% increase in population.

Polynomials-and-rational-expressions/124992: 3x to the second power +x-5 1 solutions Answer 91626 by checkley71(8403)   on 2008-02-05 09:50:34 (Show Source): You can put this solution on YOUR website! 3X^2+X-5 USING THE QUADRATIC EQUATION: X=(-1+-SQRT[1^2-4*3*-5)/2*3 X=(-1+-SQRT[1+60])/6 X=(-1+-SQRT61)/6 X=(-1+-7.81)/6 X=-1+7.81)/6 X=6.81/6 X=1.135 ANSWER. X=(-1-7.81)/6 X=-8.81/6 X=-1.468 ANSWER.

Sequences-and-series/124996: find two numbers consecutive pairs whose product is 80 1 solutions Answer 91625 by checkley71(8403)   on 2008-02-05 09:43:00 (Show Source): You can put this solution on YOUR website! MAYBE THIS IS NOT THE CORRECT ANSWER BECAUSE THE PROBLEM SHOULD BE: "TWO COSECUTIVE ODD OR EVEN NUMBERS WHOSE PRODUCT IS 80" -------------------------------------------------------------- LET X & (X+1) BE THE 2 CONSECUTIVE NUMBERS. X(X+1)=80 X^2+X-80=0 USING THE QUADRATIC EQUATION WE GET: X=(-1+-SQRT[1^2-4*1*-80])/2*1 X=(-1+-SQRT[1+320])/2 X=(-1+-SQRT[321])/2 X=(-1+-17.92)/2 X=(-1+17.92)/2 X=16.92/2 X=8.46 ANSWER. X=(-1-17.92)/2 X=-18.92/2 X=-9.46 ANSWER.

Sequences-and-series/124994: the sum of two numbers is 20 and the sum of their square is 208. find these numbers 1 solutions Answer 91622 by checkley71(8403)   on 2008-02-05 09:30:53 (Show Source): You can put this solution on YOUR website! X+Y=20 OR X=20-Y X^2+Y^2=208 (20-Y)^2+Y^2=208 400-20Y+Y^2+Y^2=208 2Y^2-20Y+400-208=0 2X^2-20Y+192=0 2(X^2-10X-96)=0 2(X-16)(X+6)=0 X-16=0 X=16 ANSWER. X+6=0 X=-6 ANSWER.

Equations/124991: Help. the problem is (3x -2y)*the second power the answer is 9x* -12xy +4y* and I'm not getting that, I'm missing a step showing -12xy is there anyway you can break down each step to show 9x* -12xy +4y 1 solutions Answer 91621 by checkley71(8403)   on 2008-02-05 09:23:54 (Show Source): You can put this solution on YOUR website! I'LL GIVE YOU AN EXAMPLE THAT MIGHT EXPLAIN HOW I GOT THE MIDDLE TERMS. MULTIPLY 63 BY 22. -------63 -------22 --------------------------------- ------126 -----126 -------------------------------- -----1386 WHERE DID I GET THE 3 & 8? ANSWER - BY ADDING THE INTERIM (MIDDLE) VALUES. ONE WAY TO SEE HOW THIS IS ACCOMPLISHED IS TO MULTIPLY USING THE OLD FASHIONED METHOD AS FOLLOWS: 3X-2Y 3X-2Y ------------------------------ 9X^2-6XY-6XY+4Y^2 THE 9X^2=3X*3X, THE -6XY=3X*-2Y, THE OTHER -6XY=-2Y*3X & -2Y*-2Y=4Y^4 NOW COMBINE THE XY TERMS. 9X^2-12XY+4Y^2

Polynomials-and-rational-expressions/124993: xsquare -4xy-5ysquare 1 solutions Answer 91620 by checkley71(8403)   on 2008-02-05 09:19:15 (Show Source): You can put this solution on YOUR website! X^2-4XY-5Y^2 (4X-5Y)(X+Y) ANSWER.

Inequalities/124990: my problem is 4/3r-3<+2/3-1/3r. 1 solutions Answer 91619 by checkley71(8403)   on 2008-02-05 09:11:12 (Show Source): You can put this solution on YOUR website! 4/3r-3<2/3-1/3r IF YOU MEAN: 4R/3-3<2/3-R/3 4R/3+R/3<2/3+3 5R/3<2/3+9/3 5R/3<11/3 CANCELLING OUT THE EQUAL DENOMINATORS WE GET: 5R<11 R<11/5 ANSWER. PROOF: LET R=10/5 OR 2 4*2/3-3<2/3-2/3 8/3-3<0 8/3-9/3<0 -1/3<0

Money_Word_Problems/124885: This question is from textbook Karen invested some money at 9% annual simple interest and $250 more than that amount at 10% interest. If her total yearly interest from both accounts was $101, how much was invested at each rate 1 solutions Answer 91618 by checkley71(8403)   on 2008-02-05 09:02:19 (Show Source): You can put this solution on YOUR website! .09x+.10(x+250)=101 .09x+.10x+25=101 .19x=101-25 .19x=76 x=76/.19 x=$400 invested @ 9%. 400+250=650 amount invested @ 10%. proof. .09*400+.10*650=101 36+65=101 101=101

Linear-equations/124933: This question is from textbook 2y=6x+5 1 solutions Answer 91617 by checkley71(8403)   on 2008-02-05 08:54:39 (Show Source): You can put this solution on YOUR website! IF THIS IS A LINE EQUATION THEN: 2Y=6X+5 Y=6X/2+5/2 Y=3X+5/2 THIS IS A LINE WITH A SLOPE=3 & A Y INTERCEPT=5/2. PROOF: (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, y = 3x +5/2).

Graphs/124910: Lane invested $10,000, part at 15% and part at 14%. If the total interest at the end of the year is $1,430, how much did she invest at 15%? 1 solutions Answer 91616 by checkley71(8403)   on 2008-02-05 08:50:11 (Show Source): You can put this solution on YOUR website! .15X+.14(10,000-X)=1,430 .15X+1,400-.14X=1,430 .01X=1,430-1,400 .01X=30 X-30/.01 X=3,000 AMOUNT INVESTED @ 15%. 10,000-3,000=7,000 AMOUNT INVESTED @ 14%. PROOF: .15*3,000+.14*7,000=1,430 450+980=1,430 1,430=1,430

Numeric_Fractions/124969: y/4 = 3 3/5 1 solutions Answer 91615 by checkley71(8403)   on 2008-02-05 08:43:03 (Show Source): You can put this solution on YOUR website! Y/4=3 3/5 Y/4=18/5 NOW CROSS MULTIPLY. 5Y=4*18 5Y=72 Y=72/5 OR 14 2/5 ANSWER.

Proportions/124977: In a car park, the ratio of red cars to green cars is 5:6, while that of green cars to blue is 3:10.Find the ratio of red cars to blue cars. 1 solutions Answer 91614 by checkley71(8403)   on 2008-02-05 08:38:22 (Show Source): You can put this solution on YOUR website! 5:6 r:g 3:10 g:b or 6:20 g:b thus: 5:6 & 6:20=5:20 or 1:4 is the ration of red to blue carrs.

Rational-functions/124983: Consider the function f(x) = x^2 + 4x +1 Find h, the x-coordinate of the vertex of this parabola. 1 solutions Answer 91613 by checkley71(8403)   on 2008-02-05 08:27:54 (Show Source): You can put this solution on YOUR website! F(X)=X^2+4X+1 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, y = x^2 +4x +1).

Miscellaneous_Word_Problems/124920: Rose's garden is a square with sides of length x feet.Next spring she plans to make it rectangular by lengthening one side 5 feet and shortening the other side by 5 feet. What polynomial represents the new area? By how much will the area of the new garden differ from that of the old garden? 1 solutions Answer 91597 by checkley71(8403)   on 2008-02-04 23:16:48 (Show Source): You can put this solution on YOUR website! A SQUARE GARDEN THAT IS X FT ON A SIDE HAS X^2FT OF AREA IF YOU SHORTEN ONE SIDE BY 5 FT & EXTEND THE OTHER SIDE BY 5 FT YOU NOW HAVE AN AREA OF: (X-5)(X+5)=X^2-25. COMPARING THE ORIGINAL AREA OF X^2 FT WITH THE NEW AREA OF (X^2-25) YOU SEE THAT YOU LOST 25 FT^2. PROOF IS IN SUBSTITUTING ANY NUMBER GREATER THAN 5 FOR X AND SOLVING THESE TWO EQUATIONS.

Graphs/124934: Allen bought 30 stamps at the post office in 39¢ and 24¢ denominations. If the total cost of the stamps was $9.90, how many 39¢ stamps did Allen buy? 1 solutions Answer 91595 by checkley71(8403)   on 2008-02-04 23:11:54 (Show Source): You can put this solution on YOUR website! .39X+.24(30-X)=9.90 .39X+7.20-.24X=9.90 .15X=9.90-7.20 .15X=2.70 X-2.70/.15 X=18 THE NUMBER OF $.39 STAMPS BOUGHT. 30-18=12 IS THE NUMBER OF $.24 STAMPS BOUGHT. PROOF .39*18+.24*12=9.90 7.02+2.88=9.90 9.90=9.90

Human-and-algebraic-language/124942: Janet and Marcus work for a landscaping company. Their project involves making a garden with a 4-foot-wide walkway on each side of a 50-foot square piece of land. The plan for the project is shown. What is the area of the garden in square feet, not including the walkway? 1 solutions Answer 91593 by checkley71(8403)   on 2008-02-04 23:07:19 (Show Source): You can put this solution on YOUR website! A SQUARE PIECE OF LAND 50 FT. ON A SIDE IS: 50*50=2500 FT^2 IS THE TOTAL AREA. SUBTRACTING THE WALKWAY OF 4 FT. WE HAVE LEFT (50-2*4)(50-2*4)=(50-8)(50-8)=42*42=1764 FT^2 FOR THE GARDEN EXCLUDING THE WALK WAY. (THIS ASSUMES WHEN YOU SAY EACH SIDE YOU MEAN ALL 4 SIDES THEREFORE THE 50 FT. IS REDUCED BY A WALK WAY ON EACH SIDE THUS THE [2*4] SUBTRACTION).

Mixture_Word_Problems/124946: Mixing 100% antifreeze with 40% antifreeze to get 20 quarts of 50% antifreeze 1 solutions Answer 91591 by checkley71(8403)   on 2008-02-04 22:59:20 (Show Source): You can put this solution on YOUR website! X+.4(20-X)=.5*20 X+8-.4X=10 .6X=10-8 .6X=2 X=2/.6 X=3.333 QTS OF PURE ANTIFREEZE IS NEEDED TO GET A 50% MIX. PROOF 3.333+.4(20-3.333)=.5*20 3.333+.4*16.667=10 3.333+6.667=0 10=10

Graphs/124936: A principal of $5000 was invested in a savings account for 4 years. If the interest earned for the period was $400, what was the annual interest rate? 1 solutions Answer 91589 by checkley71(8403)   on 2008-02-04 22:51:42 (Show Source): You can put this solution on YOUR website! i=prt where i=interest, p=principle, r=interest rate & t=number of years. 400=5000*r*4 400=20000r r=400/20000 r=.02 or 2% is the interest rate. This assumes the rate is for the 4 years NOT an annual interest rate. An annual interest rate formula is: i=p(1+r)^t-p 400=5000(1+r)^4-5000 400+5000=5000(1+r)^4 5400=5000(1+r)^4 5400/5000=(1+r)^4 1.08=(1+r)^4 4th root of 1.08=1+r 1.019426547=1+r r=1.0194-1 r=.0194 or 1.94% if compounded annually.

Travel_Word_Problems/124932: An airplane travels 750 miles against the wind in 7.5 hours, and makes the return trip with the same wind in 3 hours. Find the rate of the wind. (Make sure to answer the question.)((This is exactly how the problem reads.)) Thank you! 1 solutions Answer 91559 by checkley71(8403)   on 2008-02-04 21:44:43 (Show Source): You can put this solution on YOUR website! 750/7.5=100 mph for the first flight. 750/3=250 mph for the return flight. let x be the value of the wind. 100+x=250-x 2x=250-100 2x=150 x=150/2 x=75 mph for the rate of the wind.

Graphs/124921: Are the following lines parallel, perpendicular, or neither? L1 with equation x – 2y = 10 L2 with equation 2x + y = 2 1 solutions Answer 91557 by checkley71(8403)   on 2008-02-04 21:39:50 (Show Source): You can put this solution on YOUR website! TO ANSWER THIS PROBLEM WE NEED TO FIND THE SLOPES OF THESE 2 LINES THUS: Y=mX+b WHHERE m=SLOPE. X-2Y=10 OR -2Y=-X+10 OR Y=-X/-2+10/-2 OR Y=X/2-5 (RED LINE)WHICH GIVES US A SLOPE=1/2. 2X+Y=2 OR Y=-2X+2 (GREEN LINE) WHICH GIVES US A SLOPE=-2. SEEING AS THESE 2 SLOPES (1/2 & -2) ARE NEGATIVE RECIPRICALS OF EACH OTHER THEN THESE 2 LINES ARE PERPENDICULAR TO ONE ANOTHER. PROOF: (graph 300x300 pixels, x from -10 to 10, y from -10 to 10, of TWO functions y = x/2 -5 and y = -2x +2).