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Recent problems solved by 'rfer'

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Linear-equations/383475: write the equation of the line passing through A (-1,6) and (3,-4)? 1 solutions Answer 271504 by rfer(12644)   on 2010-12-09 01:12:13 (Show Source): You can put this solution on YOUR website! m=-4-6/3--1=-10/4 m=-2.5 -------------- y=mx+b -4=-2.5*3+b -4=-7.5+b b=3.5 --------- y=-2.5x+3.5

Linear-equations/383429: Find the slope and Y intercept of (-4,3) (0,0) (1,-1) (3,-3) 1 solutions Answer 271502 by rfer(12644)   on 2010-12-09 01:07:25 (Show Source): You can put this solution on YOUR website! slope m=-1 y int b=0

Expressions-with-variables/383469: Find three consecutive numbers whose sum is 90. 1 solutions Answer 271500 by rfer(12644)   on 2010-12-09 01:04:34 (Show Source): You can put this solution on YOUR website! x+x+1+x+2=90 3x=87 x=29 x+1=30 x+2=31

Equations/383374: Jamal received a 20% discount when he purchased his computer. He paid $920.00 What was the regular price of the computer? 1 solutions Answer 271474 by rfer(12644)   on 2010-12-08 22:49:20 (Show Source): You can put this solution on YOUR website! 920/0.80=1150

Equations/383400: What is the answer to this equation 10g+5=11g 1 solutions Answer 271473 by rfer(12644)   on 2010-12-08 22:46:21 (Show Source): You can put this solution on YOUR website! subtract 10g g=5

Equations/383407: 4x-1(2)=5x+4 1 solutions Answer 271472 by rfer(12644)   on 2010-12-08 22:44:45 (Show Source): You can put this solution on YOUR website! x=-6

Miscellaneous_Word_Problems/383086: A shop sells compact disks for $15 per piece. If each disk costs $6 to the shop owner how much profit percent does the shop owner earn? 1 solutions Answer 271374 by rfer(12644)   on 2010-12-08 16:21:44 (Show Source): You can put this solution on YOUR website! 9/6=1.50=150%

Linear-equations/383146: 5x+3y=9 in function form 1 solutions Answer 271373 by rfer(12644)   on 2010-12-08 16:15:45 (Show Source): You can put this solution on YOUR website! 3y=-5x+9 y=-5/3x+3 f(x)=-5/3x+3

Travel_Word_Problems/383135: A car travels at an average speed of 68miles per hour. How many miles does it travel in 5hours and 15minutes? 1 solutions Answer 271371 by rfer(12644)   on 2010-12-08 16:14:08 (Show Source): You can put this solution on YOUR website! 68*5.25=357 miles

Volume/382990: what is the total area of a cylinder with a radius of 6 ft. and a height of 10 ft. ? 1 solutions Answer 271333 by rfer(12644)   on 2010-12-08 13:41:38 (Show Source): You can put this solution on YOUR website! A=3.14*6^2*10

Equations/383028: Write the equation of the line with slope -4 and y- intercept (0,9) I cam e up with y=4x+9 just want to know if i did this right 1 solutions Answer 271331 by rfer(12644)   on 2010-12-08 13:37:23 (Show Source): You can put this solution on YOUR website! slope m=-4 y=-4x+9 this slope goes down to the right

expressions/383038: Evaluate: 100 / b when b = 4 1 solutions Answer 271330 by rfer(12644)   on 2010-12-08 13:34:50 (Show Source): You can put this solution on YOUR website! 100/4=25

test/382781: 1/3x-2/5=1/4(x+3) solve for x 1 solutions Answer 271217 by rfer(12644)   on 2010-12-08 01:17:51 (Show Source): You can put this solution on YOUR website! 1/3x-2/5=1/4x+3/4 4/12x-3/12x=15/20+8/20 1/12x=23/20 x=(23/20)/(1/12) x=23/20*12/1 x=276/20 x=13 4/5

Functions/382802: Given the function k described by k(x) =x +10, find each of the following. K(0)= ___ ? 1 solutions Answer 271212 by rfer(12644)   on 2010-12-08 01:09:45 (Show Source): You can put this solution on YOUR website! k(0)=0+10 k(0)=10

Linear-equations/382805: Write an equation of the line containing the given point and parallel of the given line. Express your answer in the form y=mx+b (5,9); 4x+y=3 1 solutions Answer 271211 by rfer(12644)   on 2010-12-08 01:08:30 (Show Source): You can put this solution on YOUR website! 4*5+9=b 29=b y=-4x+29

Polynomials-and-rational-expressions/382819: me and shaira go to mall we pay for the buss for 35.00 pesos when we arrive we go to the bookstore and we buy a record book for only 35.00 pesos then we buy a chocolate for 45.00 pesos then we buy a action figure toy for 90.00 pesos then we buy a book for only 100.00 pesos then we buy a clothes for only 1,200.00 the money we have is 10,000.00 pesos how much we will pay for all the billings and the change???? 1 solutions Answer 271209 by rfer(12644)   on 2010-12-08 01:03:31 (Show Source): You can put this solution on YOUR website! purchases = 1505 change= 10000-1505=8495.00

Equations/382806: please help 1/3(18x+15)=.25(4x+12) 1 solutions Answer 271207 by rfer(12644)   on 2010-12-08 00:59:11 (Show Source): You can put this solution on YOUR website! 6x+5=x+3 5x=-2 x=-2/5 x=-0.4

test/382817: If I earned 1600 and I spend 224 and I invest 1000 I put the remaining in a savings what percent of my earnings did I put in a savings? 1 solutions Answer 271205 by rfer(12644)   on 2010-12-08 00:56:04 (Show Source): You can put this solution on YOUR website! 1600-224-1000=376 376/1600=0.235=23.5%

Equations/382820: a+1 3/4 = 6 1/4 1 solutions Answer 271203 by rfer(12644)   on 2010-12-08 00:53:11 (Show Source): You can put this solution on YOUR website! a+7/4=25/4 a=25/4-7/4 a=18/4 a=4 1/2

Geometry_Word_Problems/382822: Two angles are complementary. The measure of one is 9 more than twice the other. find the measure of each angle. 1 solutions Answer 271202 by rfer(12644)   on 2010-12-08 00:50:57 (Show Source): You can put this solution on YOUR website! x+2x+9=90 3x=81 x=27 2x+9=63

Numbers_Word_Problems/382831: Use the clues to find each number. The product of its digits is 24. It is odd. The difference between its digits is 5. 1 solutions Answer 271201 by rfer(12644)   on 2010-12-08 00:48:42 (Show Source): You can put this solution on YOUR website! -3*-8=24

Miscellaneous_Word_Problems/382827: The perimeter of a square is 32 feet. What is the area of the square? 1 solutions Answer 271198 by rfer(12644)   on 2010-12-08 00:46:53 (Show Source): You can put this solution on YOUR website! 32/4=8 8^2=64 sq ft

Probability-and-statistics/382708: John has made 80% of his free throws throughout his career.He has made 1500 successful free throws.How many attempts has he made? 1 solutions Answer 271150 by rfer(12644)   on 2010-12-07 20:56:24 (Show Source): You can put this solution on YOUR website! 1500/.8=1875

Graphs/382613: Write an equation in slope-intercept form for the line that contains each pair of points below (6,22) and (2,14) 1 solutions Answer 271148 by rfer(12644)   on 2010-12-07 20:53:37 (Show Source): You can put this solution on YOUR website! m=14-22/2-6 m=-8/-4 m=2 ----------------------- y=mx+b solve for b 14=2*2+b b=10 ------------------ y=2x+10

Graphs/382598: Write an equation in slope-intercept for the line that fits this description: contains the origin and has a slope of 2/3 1 solutions Answer 271146 by rfer(12644)   on 2010-12-07 20:49:27 (Show Source): You can put this solution on YOUR website! y=2/3x

Matrices-and-determiminant/382700: determine values of the variables, if possible 4[-a]+[-a]=[5] 2b -2b -2 c 5 1 solutions Answer 271145 by rfer(12644)   on 2010-12-07 20:47:23 (Show Source): You can put this solution on YOUR website! -4a-a=5 -5a=5 a=-1 ------------------ -2 the b goes away -------------

Graphs/382610: Write an equation in slope-intercept form for the line that contains each pair of points below (-9,-1) and (3,7) 1 solutions Answer 271143 by rfer(12644)   on 2010-12-07 20:45:13 (Show Source): You can put this solution on YOUR website! m=7--1/3--9 m=8/12 m=2/3 --------------------- y=mx+b 7=2/3*3+b 7=6/3+b 5=b ---------------- y=2/3x+5

Triangles/382681: I was woundering if i can get help on solving for x with a triangle. 1 solutions Answer 271140 by rfer(12644)   on 2010-12-07 20:33:57 (Show Source): You can put this solution on YOUR website! post the question

Polygons/382616: Okay, I have to find the area of a regular polygon. This question is: Find the area of a pentago with a side of 10 ft. I keep getting 216.5, but the answer is 172. How did I mess up? 1 solutions Answer 271136 by rfer(12644)   on 2010-12-07 20:25:13 (Show Source): You can put this solution on YOUR website! Use the equation. A=1.72048*s^2 A=1.72048*10^2 A=1.72048*100 A=172.048 round off to A=172 This works for a regular pentagon

Exponents/382627: -3x+10x+4-7X 1 solutions Answer 271126 by rfer(12644)   on 2010-12-07 20:07:39 (Show Source): You can put this solution on YOUR website! If your 7X should be 7x then the answer is 4

Graphs/382611: Write an equation in slope-intercept form for the line that contains each pair of points below (6,-9) and (3,-5) 1 solutions Answer 271123 by rfer(12644)   on 2010-12-07 20:05:30 (Show Source): You can put this solution on YOUR website! m=-5--9/3-6 m=4/-3 m=-4/3 --------------- -5=-4/3(3)+b -5=-4+b b=-1 ------------------- y=-4/3x-1