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Equations/491473: How do you differentiate whether to turn a negative sign into a positive or keeping it the same. For example 12c + 9b - (6c - 7b). It comes out to 6c+16b how do you get +16b? 1 solutions Answer 334673 by rfer(12652)   on 2011-09-05 15:11:21 (Show Source): You can put this solution on YOUR website! 12c+9b-6c+7b 6c+16b You can't get there from here!

Numeric_Fractions/491483: x + 11/9 = - 7/9 1 solutions Answer 334671 by rfer(12652)   on 2011-09-05 15:07:08 (Show Source): You can put this solution on YOUR website! x=-7/9-11/9 x=-18/9 x=-2

Equations/491530: Factor out the greatest common factor from the expression -36m2n3 – 60mn4 + 18m4n2 1 solutions Answer 334670 by rfer(12652)   on 2011-09-05 15:04:03 (Show Source): You can put this solution on YOUR website! 6mn(-6mn^2-10n^3+3m^3n)

Equations/491534: Can someone help? Factor the following expression into a product of two binomials: 64x^2-64x+16 1 solutions Answer 334667 by rfer(12652)   on 2011-09-05 15:00:29 (Show Source): You can put this solution on YOUR website! 16(-2x+1)(-2x+1)

Percentage-and-ratio-word-problems/491541: Judy bought a coat at a 15% discount sale for $68. What was the original price of the coat? 1 solutions Answer 334663 by rfer(12652)   on 2011-09-05 14:56:43 (Show Source): You can put this solution on YOUR website! 68/0.85=$80

Equations/491536: Completely factor the following expression: 9y2 – 16z2 1 solutions Answer 334662 by rfer(12652)   on 2011-09-05 14:55:52 (Show Source): You can put this solution on YOUR website! =(3y+4z)(3y-4Z)

Miscellaneous_Word_Problems/491517: The speed of sound in air s, in ft/s, is given by the formula s=1005+1.1t, where t is the temperature in degrees Fahrenheit. a. solve the formula for t b. find the Fahrenheit temperature at which the speed of sound is 1100 ft/s c. The relationship between the temperature in degrees Fahrenheit F and degrees Celsius C is given by the formula F=9/5C+32. Solve the formula for C d. Find the Celsius temperature at which the speed of sound is 110 ft/s. 1 solutions Answer 334658 by rfer(12652)   on 2011-09-05 14:51:54 (Show Source): You can put this solution on YOUR website! A) (s-1005)/1.1=t B) (1100-1005)/1.1=t 95/1.1=t 86.36 degrees C) C=5/9(F-32) C=5/9(86.36-36) C=5/9*50.36 C=28 degrees D) You do this one. Good luck

Angles/491510: If the measure of one angle is twice the measure of its supplement, than how many angles are there, what is there relationship and how can you use algebra to solve it? 1 solutions Answer 334656 by rfer(12652)   on 2011-09-05 14:45:08 (Show Source): You can put this solution on YOUR website! x+2x=180 3x=180 x=60 2x=120

Angles/491511: two angles are supplementary. One angle measures 12° more than the other. Find the measures of the angles. 1 solutions Answer 334654 by rfer(12652)   on 2011-09-05 14:43:33 (Show Source): You can put this solution on YOUR website! x+x+12=180 2x=168 x=84 x+12=96

Expressions-with-variables/491514: How do I bring down to its lowest term 4[x+2(6-x)] 1 solutions Answer 334653 by rfer(12652)   on 2011-09-05 14:42:02 (Show Source): You can put this solution on YOUR website! 4[x+12-2x] 4[-x+12] -4x+48

Miscellaneous_Word_Problems/491526: how do i find the perimeter and area of a rectangular garden with the lenth of 13 feet and a with 8 feet 1 solutions Answer 334650 by rfer(12652)   on 2011-09-05 14:38:57 (Show Source): You can put this solution on YOUR website! P=2W=2L P=2*8+2*13 P=42 ft

Numbers_Word_Problems/491527: the larger of two numbersis 7 more than the smaller. The larger number plus five times the smaller equals 67 1 solutions Answer 334649 by rfer(12652)   on 2011-09-05 14:37:33 (Show Source): You can put this solution on YOUR website! x+7+5x=67 6x=60 x=10 x+7=17

Miscellaneous_Word_Problems/491520: 28/42 - 2\5 =?? 1 solutions Answer 334646 by rfer(12652)   on 2011-09-05 14:33:23 (Show Source): You can put this solution on YOUR website! FOR EASE OF OPERATION, REDUCE 28/42 TO 2/3, then find the common denominator 2/3-2/5= 10/15-6/15=4/15

Money_Word_Problems/491522: The number of payments varies inversely with the amount of equal payments. If the number of payments is 36 when the amount of each payment is $240, how much will each payment be if 48 payments are made? Please help, thanks. 1 solutions Answer 334644 by rfer(12652)   on 2011-09-05 14:29:52 (Show Source): You can put this solution on YOUR website! 36*240=48X 8640=48X X=$180

Matrices-and-determiminant/491415: What is the solution to the problem (2t-7)(2t-7)? 1 solutions Answer 334634 by rfer(12652)   on 2011-09-05 12:05:50 (Show Source): You can put this solution on YOUR website! 4t^2-14t-14t+49 4t^2-28t+49

Matrices-and-determiminant/491417: What's the solution to (-5x+7)(x+9) 1 solutions Answer 334633 by rfer(12652)   on 2011-09-05 12:03:12 (Show Source): You can put this solution on YOUR website! -5x^2-45x+7x+63 -5x^2-38x+63

Matrices-and-determiminant/491431: what's (x+7)^2 1 solutions Answer 334632 by rfer(12652)   on 2011-09-05 12:00:42 (Show Source): You can put this solution on YOUR website! (x+7)(x+7) x^2+7x+7x+49 x^2+14x+49

Matrices-and-determiminant/491426: what's the solution to (-5x+7)-(x^2+x-2) 1 solutions Answer 334631 by rfer(12652)   on 2011-09-05 11:59:11 (Show Source): You can put this solution on YOUR website! -x^2-6x+9

Matrices-and-determiminant/491423: What's the solution to (x^6-5)+(x^6+5) 1 solutions Answer 334629 by rfer(12652)   on 2011-09-05 11:51:45 (Show Source): You can put this solution on YOUR website! =2x^6

real-numbers/491246: 12+(-7) 1 solutions Answer 334548 by rfer(12652)   on 2011-09-04 23:18:20 (Show Source): You can put this solution on YOUR website! =5

Graphs/491210: What is the slope and y-intercept for y=-3/7x-10/9 1 solutions Answer 334547 by rfer(12652)   on 2011-09-04 23:17:49 (Show Source): You can put this solution on YOUR website! slope m=-3/7 y intercept b=-10/9

expressions/491093: 28t−(24t+87) simplify 1 solutions Answer 334522 by rfer(12652)   on 2011-09-04 21:10:39 (Show Source): You can put this solution on YOUR website! 28t-24t-87 4t-87

Inequalities/491094: Please solve using Multiplication Principle Thank you in advance. -2x<-8 1 solutions Answer 334521 by rfer(12652)   on 2011-09-04 21:08:32 (Show Source): You can put this solution on YOUR website! -2x < -8 x < -8/-2 x < 4

Inequalities/491095: Please solve using Addition and Multiplication principles and Please show work. Thank you in advance. 4x - 6 > -6 1 solutions Answer 334518 by rfer(12652)   on 2011-09-04 21:07:23 (Show Source): You can put this solution on YOUR website! 4x > -6+6 4x > 0 x > 0/4 x > 0

Inequalities/491099: Please help me with this algebra problem. Thank you in advance. Please solve the equation and show all work Please make sure the answer is in simplist form. 1/7 + x = 2 1 solutions Answer 334517 by rfer(12652)   on 2011-09-04 21:04:02 (Show Source): You can put this solution on YOUR website! x=14/7-1/7 x=13/7 x=1 6/7

test/491150: n/7.2 + 4.5 = 6.4 1 solutions Answer 334516 by rfer(12652)   on 2011-09-04 21:00:29 (Show Source): You can put this solution on YOUR website! n/7.2=6.4-4.5 n/7.2=1.9 n=1.9*7.2 n=13.68

test/491183: Help me break down this math problem. I know the answer is 2. I need to know how they got this answer. 2/3-x/5=4/15 1 solutions Answer 334515 by rfer(12652)   on 2011-09-04 20:58:03 (Show Source): You can put this solution on YOUR website! -x/5=4/15-2/3 -x/5=4/15-10/15 -x/5=-6/15 -x=-6/15*5/1 -x=-30/15 x=2

Number-Line/491152: b-2(b-12)less then or equal to 7b. 1 solutions Answer 334514 by rfer(12652)   on 2011-09-04 20:55:19 (Show Source): You can put this solution on YOUR website! b-2b+24 <= 7b 24 <= 8b 24/8 <= b 3 <= b

Graphs/491177: graph the equation 6x+6y=30 by finding the intercepts. My teacher has given us the answers, but I do not understand how I am supposed to figure this out without just copying the answer. 1 solutions Answer 334512 by rfer(12652)   on 2011-09-04 20:53:02 (Show Source): You can put this solution on YOUR website! x intercept is when y=0 y intercept is when x=0 ------------ 6x+6Y=30 6x+6*0=30 6x+0=30 x=30/6 x=5 (5,0) ------------ because the numbers are the same y intercept = (0,5)

Percentage-and-ratio-word-problems/491155: I need the formula to calculate a loan balance as payments are made. Principal = 150,000 Interest rate = 8.75 Term = 30 years 1 solutions Answer 334511 by rfer(12652)   on 2011-09-04 20:48:51 (Show Source): You can put this solution on YOUR website! R=(Pi/12)/(1-(1+i/12)^-n) P=principal i=interest rate per pay period per yr. n=number of payments R=regular payment R=(150000*0.00729)/1-(1.00729)^-360 R=1093.5/1-0.0732 R=1093.5/0.9268 R=$1,179.87

Miscellaneous_Word_Problems/491158: The larger of two numbers is 6 times the smaller. Their sum is 147. Find the numbers. 1 solutions Answer 334508 by rfer(12652)   on 2011-09-04 20:39:44 (Show Source): You can put this solution on YOUR website! x+6x=147 7x=147 x=147/7 x=21 6x=126