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Linear-equations/459441: Please help me solve this equation : what is the distance between (-2,5) , (3,1) ? 1 solutions Answer 315058 by rfer(12644)   on 2011-06-09 17:22:17 (Show Source): You can put this solution on YOUR website! 5^2+4^2=c^2 25+16=41 sqrt 41=6.4

Polynomials-and-rational-expressions/459442: Please help me with this problem : what is the slope intercept of points (-1,4) and (5,2) ? 1 solutions Answer 315056 by rfer(12644)   on 2011-06-09 17:18:59 (Show Source): You can put this solution on YOUR website! m=(2-4)/(5--1) m=-2/6 m=-1/3 ---------------- y=mx+b 2=-1/3*5+b 2=-5/3+b b=2+5/3 b=12/6+10/6 b=18/6 b=3 ------------- y=-1/3x+3

Coordinate-system/459310: Write an equation for the line with slope 3 going through the point (1,-2). How would I do this? I'm 46 and trying to refresh my algebra skills. Thanks 1 solutions Answer 314984 by rfer(12644)   on 2011-06-09 13:47:38 (Show Source): You can put this solution on YOUR website! first find the y intercept y=mx+b -2=3*1+b -2=3+b b=-5 ---------------- put information in equation. y=3x-5

Trigonometry-basics/459190: You are standing 75 meters from the base of the Jin Mao in Shangai, China. You estimate that the angle of elevation to the top of the building is 80. What is the approximate height of the building? Suppose one of your friends is at the top of the building. What is the distance between you and your friend? i found the answer to the first question its 425.3.. i have no idea how to do the second part of the problem... 1 solutions Answer 314922 by rfer(12644)   on 2011-06-08 23:50:47 (Show Source): You can put this solution on YOUR website! 75^2+425.3^2=c^2 5625+180880=1886505 sqrt 1886505=1373.5 meters

Money_Word_Problems/459123: (1) How much money will you have in an account after 10 years if you deposit $5000 into the account and it pays 5% annual interest (a) compounded quarterly? (b) if it is simple interest (This can be done even without a fancy calculator.) 1 solutions Answer 314920 by rfer(12644)   on 2011-06-08 23:41:47 (Show Source): You can put this solution on YOUR website! A=5000(1+0.05/4)^4*10 A=5000*1.6436 A=$8,218 -------------- I=5000*0.05*10 I=2500 5000+2500=$7,500

Equations/459184: x+4/7>3 1 solutions Answer 314918 by rfer(12644)   on 2011-06-08 23:31:45 (Show Source): You can put this solution on YOUR website! x > 3-4/7 x > 63/21-12/21 x > 51/21 x > 2 3/7

Travel_Word_Problems/459151: sue and may ride bikes in opposite directions. may rides 5 mph faster then sue. if they are 25 miles apart after one hour, find sues rate of speed 1 solutions Answer 314917 by rfer(12644)   on 2011-06-08 23:29:01 (Show Source): You can put this solution on YOUR website! x+x+5=25 2x=20 x=10mph x+5=15mph

Numeric_Fractions/459178: the average of two numbers, aand b, is given by. A=a+b/2 if the average of two numbers is 73 and if one og f the numbers is 59, then what is the other number? 1 solutions Answer 314916 by rfer(12644)   on 2011-06-08 23:26:54 (Show Source): You can put this solution on YOUR website! 73=(59+b)/2 146=59+b b=87

Surface-area/459095: 11 5/6 / 7 1 solutions Answer 314860 by rfer(12644)   on 2011-06-08 19:39:58 (Show Source): You can put this solution on YOUR website! 71/6*1/7=71/42 =1 29/42

Human-and-algebraic-language/459049: An apartment building contains 12 units consisting of one- and two-bedroom apartments that rent for $360 and $450 per month, respectively. When all units are rented, the total monthly rental is $4,950. What is the number of two-bedroom apartments? A. 3 B. 4 C. 5 D. 6 E. 7 1 solutions Answer 314859 by rfer(12644)   on 2011-06-08 19:38:07 (Show Source): You can put this solution on YOUR website! x+y=12 y=12-x 360x+450y=4950 360x+450(12-x)=4950 360x+5400-450x=4950 -90x=-450 x=5 y=12-5=7 two bed

Probability-and-statistics/459067: i need help solving this. Thomas has a set of 26 alphabet cards, each having a different letter of the alphabet on it. He randomly draws one card and then rolls a fair die, numbered from 1 to 6. What is the probability he draws a card with a vowel (a, e, i, o, u) on it and then rolls a number divisible by 2? 1 solutions Answer 314844 by rfer(12644)   on 2011-06-08 18:39:51 (Show Source): You can put this solution on YOUR website! 5/26*3/6=15/156=5/52

Proportions/459001: find the unit rate of $11.58 for 8.2 galons 1 solutions Answer 314830 by rfer(12644)   on 2011-06-08 15:57:28 (Show Source): You can put this solution on YOUR website! 11.58/8.2=$1.412 per gal

Average/458945: evaluate this polynomail if a=2 b=-3 c=4 d=-5 ab+cd 1 solutions Answer 314823 by rfer(12644)   on 2011-06-08 15:03:56 (Show Source): You can put this solution on YOUR website! 2*-3+4*-5 -6+-20=-26

Distributive-associative-commutative-properties/458957: A jet liner hits an air pocket & drops 216 feet. After climbing 173 feet, it drops another 119 feet. What is its overall vertical change? 1 solutions Answer 314821 by rfer(12644)   on 2011-06-08 15:02:02 (Show Source): You can put this solution on YOUR website! -216+173-119=-162 ft

Polynomials-and-rational-expressions/458967: Simplify a - {5b - [a - (3b - 2c) + c - (a - 2b - c)]}. Possible answers below show me how u got the answer! -a - 6b + 4c a - 6b + 4c a - 10b + 4c -a + 10b + 4c 1 solutions Answer 314820 by rfer(12644)   on 2011-06-08 14:58:36 (Show Source): You can put this solution on YOUR website! a-{5b-[a-3b+2c+c-a+2b+c]} a-{5b-a+3b-2c-c+a-2b-c} a-{6b-4c} a-6b+4c

test/458753: In a class of 44 students, the number of females is one fewer than twice the number of males. How many females and how many males are there in the class? 1 solutions Answer 314688 by rfer(12644)   on 2011-06-07 23:10:22 (Show Source): You can put this solution on YOUR website! x+2x-1=44 3x=45 x=15 boys 29 girls

Percentage-and-ratio-word-problems/458691: If a shirt you buy at the store is $90.00 and there is a 5% sale there was also a 17% tax. What is the final price? 1 solutions Answer 314671 by rfer(12644)   on 2011-06-07 21:29:41 (Show Source): You can put this solution on YOUR website! 90*0.95*1.17=$100.04

Triangles/458721: If a right triangle has a hypotenuse of 12cm and one leg of 9cm, what is the length of the other leg? 1 solutions Answer 314666 by rfer(12644)   on 2011-06-07 21:25:24 (Show Source): You can put this solution on YOUR website! 144-81=63 sq rt 63=7.9

Triangles/458720: 1 solutions Answer 314665 by rfer(12644)   on 2011-06-07 21:23:22 (Show Source): You can put this solution on YOUR website! 12, 16, 20 triangle

Angles/458669: if angle abc = 78 what is the measurement of the angle supplementary to angle abc? 1 solutions Answer 314618 by rfer(12644)   on 2011-06-07 20:02:55 (Show Source): You can put this solution on YOUR website! 180-78=102

Graphs/458666: What is the point-slope form of an equation of the line that passes through (4,-3) and (2,1)? 1 solutions Answer 314617 by rfer(12644)   on 2011-06-07 20:01:47 (Show Source): You can put this solution on YOUR website! slope m=(1--3)/(2-4) m=4/-2 m=-2 -------------- y=mx+b 1=-2*2+b 1=-4+b b=5 ---------- y=-2x+5

Graphs/458664: What equation contains the points (-1,-8) and (-9,-21) 1 solutions Answer 314616 by rfer(12644)   on 2011-06-07 19:58:47 (Show Source): You can put this solution on YOUR website! slope m=(-21--8)/(-9--1) m=-13/-8 m=13/8 --------------- y=mx+b -9=13/8*-1+b -9=-13/8+b -9+13/8=b -72/8+13/8=B -59/8=b b=-7.4 ------------ y=13/8x-7.4

test/458633: Got it. Five times the sum of a number and -1 is the same as 6 times the number. Find the number 1 solutions Answer 314612 by rfer(12644)   on 2011-06-07 19:52:53 (Show Source): You can put this solution on YOUR website! 5(x-1)=6x 5x-5=6x x=-5

Money_Word_Problems/458639: a principal of 5000 is invested at 3.5% intrest rate annually after 5 years how much would the investment be worth? 1 solutions Answer 314609 by rfer(12644)   on 2011-06-07 19:50:08 (Show Source): You can put this solution on YOUR website! A=5000(1.035)^5 A=5000*1.1877 A=$5,938.50

Miscellaneous_Word_Problems/458641: Hello, Can someone help me solve this problem? Translate to an algebraic twice n The translation is___? 1 solutions Answer 314608 by rfer(12644)   on 2011-06-07 19:47:29 (Show Source): You can put this solution on YOUR website! =2n

Travel_Word_Problems/458648: A car travels at 45 miles per hour for 90 minutes. How far has it traveled in this time? 1 solutions Answer 314607 by rfer(12644)   on 2011-06-07 19:46:15 (Show Source): You can put this solution on YOUR website! 45*1.5=67.5 miles

Polynomials-and-rational-expressions/458652: Short answer. Find the product: -4x (8x^3 + 9x^2 – 5x + 3) 1 solutions Answer 314606 by rfer(12644)   on 2011-06-07 19:44:22 (Show Source): You can put this solution on YOUR website! =-32x^4-36x^3+20x^2-12x

Graphs/458659: How can you solve a word problem that only explains the equation and does not show it in number form? 1 solutions Answer 314605 by rfer(12644)   on 2011-06-07 19:42:51 (Show Source): You can put this solution on YOUR website! post it so we can see it.

Triangles/458655: The angles of a triangle are in the ratio of 2:3:7. How do I find the measures of the angles? 1 solutions Answer 314603 by rfer(12644)   on 2011-06-07 19:42:02 (Show Source): You can put this solution on YOUR website! 2x+3x+7x=180 12x=180 x=15 2x=30 3x=45 7x=105

Proportions/458656: how to solve using a proportion to find 5% of 320. 1 solutions Answer 314601 by rfer(12644)   on 2011-06-07 19:40:28 (Show Source): You can put this solution on YOUR website! 320*0.05=16

Triangles/458600: How do I find if a triangle is a right triangle through the side lengths 6,8,10? 1 solutions Answer 314600 by rfer(12644)   on 2011-06-07 19:38:42 (Show Source): You can put this solution on YOUR website! 36+64+100 sqrt 100=10, yes it is a right triangle This is a classic 3, 4, 5 triangle.