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Quadratic_Equations/139337: Help me translate this into a quadratic equation and solve. Thanks!
Three consecutive even integers are such that the square of the third is 76 more than the square of the second. Find the three integers. 1 solutions
Answer 101614 by checkley77(12569) on 2008-04-30 15:21:15 (Show Source):
You can put this solution on YOUR website!LET X, X+2, & X+4 BE THE 3 CONSECUTIVE EVEN INTEGERS.
(X+4)^2=(X+2)^2+76
X^2+8X+16=X^2+4X+4+76
8X-4X=4+76-16=0
4X=64
X=64/4
X=16 ANSWER.
16+2=18 FOR THE MIDDLE NUMBER.
16+4=20 FOR THE THIRD NUMBER.
PROOF:
20^2=18^2+76
400=324+76
400=400
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Money_Word_Problems/139345: Some students planned for a get-together. The budget for food was $500. Five of the students failed to come because of the distance, therfore the cost of food for each member increased by $5. How many students attended the get-together? 1 solutions
Answer 101608 by checkley77(12569) on 2008-04-30 14:55:30 (Show Source):
You can put this solution on YOUR website!500/X=500/(X-5)-5
500/X=(500-5[X-5])/(X-5)
500/X=(500-5X+25]/(X-5)
X(500-5X+25)=500(X-5)
500X-5X^2+25X=500X-2500
-5X^2+25X+2500=0
-5(X^2-5X-500)=0
5(X-25)(X+20)=0
X-25=0
X=25 ANSWER.
PROOF:
500/25=500/(25-5)-5
20=500/20-5
20=25-5
20=20
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Travel_Word_Problems/139346: Steve traveled 600 miles at a certain speed. Had he gone 20mph faster, the trip would have taken 1 hour less. Find the speed of his vehicle? 1 solutions
Answer 101606 by checkley77(12569) on 2008-04-30 14:37:11 (Show Source):
You can put this solution on YOUR website!600/X-600/(X+20)=1
(600[X+20]-600*X)/X(X+20)=1
(600X+12000-600X)/(X^2+20X)=1 NOW CROSS MULTIPLY
X^2+20X=12,000
X^2+20X-12,000=0
(X+120)(X-100)=0
X-100=0
X=100 SPEED OF THE TRIP.
PROOF:
600/100-600/120=1
6-5=1
1=1
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Travel_Word_Problems/139347: Rita rows 12km upstream and 12 km downstream in 3 hours. The speed of her boat in still water is 9km/hour. Find the speed of the stream. 1 solutions
Answer 101605 by checkley77(12569) on 2008-04-30 14:27:12 (Show Source):
You can put this solution on YOUR website!12/(9-X)+12/(9+X)=3
(12[9+X]+12[9-X])/(9-X)(9+X)=3
(108+12X+108-9X)/(81-X^2)=3 NOW CROSS MULTIPLY.
3(81-X^2)=108+12X+108-9X
243-3X^2=216+3X
-3X^2-3X+243-216=0
-3X^2-3X+27=0
-3(X^2+X-9)=0
USING THE QUADRATIC EQUATION WE GET:
X=(-1+-SQRT[1^1-4*1*-9])/2*1
X=(-1+-SQRT[1+36)/2
X=(-1+-SQRT37)/2
X=(-1+-6.083)/2
X=(-1+6.083)/2
X=5.083/2
X=2.54 ANSWER FOR THE SPEED OF THE CURRENT.
PROOF:
12/(9-2.54)+12/(9+2.54)=3
12/6.45+12/11.54=3
1.86+1.04=3
2.9~3
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Volume/139359: A rectangular peice of sheet metal measures 26 in. by 20 in. A square measuring 2 in. by 2 in. is cut out of each corner, and the sides are folded to form a box. What is the volume of the box? Please help because this is really difficult!!!!!!!!!! 1 solutions
Answer 101603 by checkley77(12569) on 2008-04-30 14:00:31 (Show Source):
You can put this solution on YOUR website!THE BEST WAY TO MANAGE THESE TYPE OF PROBLEMS IS TO DRAW A SKETCH OF THE 26 BY 20 IN SHEET METAL AND THE 4 CORNERS CUT OUT.
------------------------------------------------------------------------------
26 IN. BY 20 IN. PIECE OF SHEET METAL WITH 2 IN. CORNERS CUT OUT NOW HAS A LENGTH OF 26-4=22 IN. & 20-4=16 IN. FOR THE WIDTH & 2 IN. FOR THE HEIGHT.
THE VOLUME OF THIS BOX IS:
22*16*2=704 IN^3.
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test/139362: This question is from textbook MASTER THE GED
IT IS A VERBAL STRATEGIES
CIRCUMFERENCE: THE CIRCUMFERENCE OF THE CLOCK WAS 42 INCHES. FIND THE DIAMETER IN INCHES.
(1) 7.5
(2) 13.4
(3) 38.9
(4) 45.14
(5) 131.9 1 solutions
Answer 101598 by checkley77(12569) on 2008-04-30 13:36:22 (Show Source):
You can put this solution on YOUR website!CIRCUMFERENCE=42 INCHES
2PI*R=42
2*3.14*R=42
6.28R=42
R=42/6.28
R=6.69 IS THE RADIUS.
2*6.69=13.38 INCHES IS THE DIAMETER OF THE CLOCK.
ANSWER 2) 13.4 IS THE CORRECT ANSWER.
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test/139221: Taya and Jed collect coins. The ratio of the number of coins in their collections, in some order, is 4 to 3. If Taya has 60 coins in her collection, how many coins could Jed have? 1 solutions
Answer 101528 by checkley77(12569) on 2008-04-29 18:36:35 (Show Source):
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Exponents/139238: Please help me solve this question, long time i don't divide polinomians, i will appreciate it. thank you.
20a^2+7ab-3b^2/4a-b 1 solutions
Answer 101526 by checkley77(12569) on 2008-04-29 18:27:51 (Show Source):
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Sequences-and-series/139230: I am in 9th grade advanced algebra 2 and am stumped on 4 of my sequence problems. The other 11 made complete sense, so now I am getting uptight....
The sequences are as follows
0,3,7,12,18,.....
2,-2,-18,-52,-110,-198,.....
4,23,64,133,236,379,568,.....
-5,-9,-19,-35,-57,-85,.... 1 solutions
Answer 101524 by checkley77(12569) on 2008-04-29 18:24:14 (Show Source):
You can put this solution on YOUR website!formula is (N+1)
here you have a sequence of +3,+4,+5,+6,+7,+8 +9
0,3,7,12,18,25,33,42
*****************************************
for the next 3 I use a very unconventional method that is too complicated to explain:
please let me know it they are acceptable?????????
2,-2,-18,-52,-110,-198,-322,-488,-702
******************************************
4,23,64,133,236,379,568,809,1108
*****************************************
-5,-9,-19,-35,-57,-85,-119,-159,-205
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Circles/139148: a round target has 3 circles with radii of 2cm, 10cm, & 20cm. what is the probability that a dart randomly thrown hits the target within the outer ring? (outer ring's radii is 20cm) 1 solutions
Answer 101520 by checkley77(12569) on 2008-04-29 17:51:32 (Show Source):
You can put this solution on YOUR website!A(20)=pir^2
A=3.14*20^2
A=3.14*400
A=1,256 total area
A(10)=3.14*10^2
A=3.14*100
A=314 area inside the 10 circle.
(1,256-314)/1,256=942/1,256=.75 or 75% chance of hitting the 20 ring.
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Radicals/139164: I need help with simplifying radical expressions. The problem is: the fifth root of . I have the answer that I got: 2* the 5th root of . Is this correct? 1 solutions
Answer 101519 by checkley77(12569) on 2008-04-29 17:43:25 (Show Source):
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Geometric_formulas/139191:
The diameter of Mars is about 4,000 mi.
A.) Find the approximate surface area.
B.) Find the approximate volume
Please Help Thanks 1 solutions
Answer 101514 by checkley77(12569) on 2008-04-29 17:23:25 (Show Source):
You can put this solution on YOUR website!SA=4pir^2
SA=4*3.14*2,000^2
SA=12.56*4,000,000
SA=50,240,000 answer.
V=4/3pir^3
V=1.333*3.14*2,000^3
V=4.186*8,000,000,000
V=3.3488*10^10
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Mixture_Word_Problems/139118: Robin's company invested its profits of $52,700, part at 13.5% and part at 15%. the total annual yield on this investment was $7432.50. How much was invested at each rate? 1 solutions
Answer 101485 by checkley77(12569) on 2008-04-29 11:17:03 (Show Source):
You can put this solution on YOUR website!.15X+.135(52,700-X)=7,432.50
.15X+7,114.5-.135X=7,432.50
.015X=7,432.50-7,114.50
.015X=318
X=318/.015
X=21,200 ANSWER FOR THE AMOUNT INVESTED @ 15%.
52,700-21,200=31,500 ANSWER FOR THE 13.5$ INVESTMENT.
PROOF:
.15*21,200+.135*31,500=7,432.50
3,180+4,252.5=7,432.5
7,432.5=7,432.5
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Quadratic_Equations/139153: What three techniques can be used to solve a quadratic equation? Please could you demonstrate all three techniques using the following equation. Thanks!
12x^2 - 10x - 42 = 0 1 solutions
Answer 101475 by checkley77(12569) on 2008-04-29 10:38:55 (Show Source):
You can put this solution on YOUR website!12x^2-10x-42=0
2(6x^2-5x-21)=0
2(2x+3)(3x-7)=0
2x+3=0
2x=-3
x=-3/2 answer.
3x-7=0
3x=7
x=7/3 answer.
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12x^2-10x-42=0
(4x+6)(6x-14)=0
4x+6=0
4x=-6
x=-6/4
x=-3/2 answer.
6x-14=0
6x=14
x=14/6
x=7/3 answer.
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12x^2-10x-42=0
using the quadratic equation:  we get:
x=(10+-sqrt[-10^2-4*12*-42])/2*12
x=(10+-sqrt[100+2016])/24
x=(10+-sqrt2116)/24
x=(10+-46)/24
x=(10+46)/24
x=56/24
x=7/3 aanswer.
x=(10-46)/24
x=-36/24
x=-3/2 answer.
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