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Expressions-with-variables/280639: solve by substitution method 4x+5y=19 x=59-9y 1 solutions Answer 204004 by rfer(12729)   on 2010-03-14 16:58:43 (Show Source): You can put this solution on YOUR website! 4(59-9y)+5y=19 236-36y+5y=19 -31y=-217 y=7 ---------------- x=-4

Equations/280637: rain A and B are traveling in the same direction on parallel tracks. A is traveling at 80mph and train B at 100mph. A passes station at 2:20 am and B at 2:38am. what time will B catch up to A? 1 solutions Answer 204003 by rfer(12729)   on 2010-03-14 16:54:31 (Show Source): You can put this solution on YOUR website! a is .3 hrs ahead approach speed is 20 mph a leads b by 24 miles 24/20=1.2 hrs=1 hr 12 min 2:38 + 1 hr 12 min = 3:50 am

Linear-systems/280641: translate to an algebraic expression the product of 25% and some number 1 solutions Answer 204000 by rfer(12729)   on 2010-03-14 16:48:44 (Show Source): You can put this solution on YOUR website! .25x

Linear-equations/280642: use the intersept to graph the equation x+2y=4 1 solutions Answer 203999 by rfer(12729)   on 2010-03-14 16:46:55 (Show Source): You can put this solution on YOUR website! (4,0) (0,2)

Quadratic_Equations/280652: Simplify: (3x^2 + 7y + 4xy – x^2) – (10y + 2(2xy) –3y + 3x(x) –1) 1 solutions Answer 203998 by rfer(12729)   on 2010-03-14 16:44:32 (Show Source): You can put this solution on YOUR website! 2x^2+7y+4xy-(7y+3x^2+4xy-1) 2x^2+7y+4xy-7y-3x^2-4xy+1 -x^2+1

Rational-functions/280697: how to solve long division 1 solutions Answer 203997 by rfer(12729)   on 2010-03-14 16:33:27 (Show Source): You can put this solution on YOUR website! post a problem

Polynomials-and-rational-expressions/280689: -9x x (10x - 8) Multiply this 1 solutions Answer 203995 by rfer(12729)   on 2010-03-14 16:32:43 (Show Source): You can put this solution on YOUR website! -9x x (10x-8) -90x^3+72x^2

Linear-equations/280679: Graph the following equation and identify the y- intercept y=x+3 tyraciajohnson@yahoo.com 1 solutions Answer 203994 by rfer(12729)   on 2010-03-14 16:30:53 (Show Source): You can put this solution on YOUR website! y int is when x=0 y=3 (0,3) y int

Length-and-distance/280692: four saucers are part of the same dinner set each has a circumference of 15.7 inches. will they fit side by side in the same box 1 solutions Answer 203993 by rfer(12729)   on 2010-03-14 16:27:05 (Show Source): You can put this solution on YOUR website! what size box?

Linear_Equations_And_Systems_Word_Problems/280690: Customers of a phone company can choose between two service plans for long distance calls. The first plan has a $15 one-time activation fee and charges 11 cents a minute. The second plan has no activation fee and charges 15 cents a minute. After how many minutes of long distance calls will the costs of the two plans be equal? 1 solutions Answer 203992 by rfer(12729)   on 2010-03-14 16:25:41 (Show Source): You can put this solution on YOUR website! 15+.11x=.15x 15=.04x x=375 minutes

Finance/280650: .03x+.05(3x)=5400 this is the equation i came up with from a word problem trying to figure out how much was invested at 3% annual interest and, 3 times that at 5% interest if the yearly total of both is 5400. I don't know what to do next though 1 solutions Answer 203990 by rfer(12729)   on 2010-03-14 16:23:09 (Show Source): You can put this solution on YOUR website! .05*3x+.03x=5400 .15x+.03x-162=5400 .18x+5400 x=30000 .03x=900 .05x*3=4500

Problems-with-consecutive-odd-even-integers/280485: Find two consecutive whole numbers whose sum is 291 1 solutions Answer 203863 by rfer(12729)   on 2010-03-13 21:37:51 (Show Source): You can put this solution on YOUR website! x+x+1=291 2x=290 x=145 x+1=146

Percentage-and-ratio-word-problems/280308: Successive discounts of 10% and 15% are equivalent to a single discount of A 12.5% b 23.5% c 25% d 76.5% e none 1 solutions Answer 203839 by rfer(12729)   on 2010-03-13 19:01:41 (Show Source): You can put this solution on YOUR website! B 23.5%

Inequalities/280237: Mary wishes to purchase a car. She wishes to spend at most $8,000. The sales tax rate in her state is 7%. Title and license plate fee is $120. What is the maximum amount she can spend for an automobile? 1 solutions Answer 203682 by rfer(12729)   on 2010-03-12 20:01:10 (Show Source): You can put this solution on YOUR website! 8000-120=7880 7880/1.07=$7364.45

Linear-systems/280247: 4y-2=33-3y 1 solutions Answer 203680 by rfer(12729)   on 2010-03-12 19:57:23 (Show Source): You can put this solution on YOUR website! 4y-2=33-3y 7y=35 y=5

Polynomials-and-rational-expressions/280244: You have 64 yards of fencing to enclose a rectangular region. Find the dimensions of the rectangle that maximize the enclosed area. i tried 2x+2y=64 so far but when i used subsitution the variables cancel out. 1 solutions Answer 203679 by rfer(12729)   on 2010-03-12 19:56:06 (Show Source): You can put this solution on YOUR website! The largest area of a rectangle is always a square. 64/4=16 16^2=256 sq yds

Reduction-of-unit-multipliers/280145: i have to use three unit multipliers to convert 300 cubic yards to cubic feet. 1 solutions Answer 203639 by rfer(12729)   on 2010-03-12 16:35:13 (Show Source): You can put this solution on YOUR website! 300/x=1/27 x=8100 cu ft

Age_Word_Problems/280191: poppy ans sesame bagels are bought to a brunch in a ratio of 3 poppy bagels to one sesame bagel. if there are 100 bagels in total, how many poppy bagels are there 1 solutions Answer 203637 by rfer(12729)   on 2010-03-12 16:30:00 (Show Source): You can put this solution on YOUR website! 75

Quadratic_Equations/280200: If a right triangle has sides (or legs) of 7 and 24, what is the hypotenuse side equal to? (Pythagorean Theorem) 1 solutions Answer 203636 by rfer(12729)   on 2010-03-12 16:28:35 (Show Source): You can put this solution on YOUR website! 7^2+24^2=c^2 49+576=c^2 625=c^2 c=25

Geometry_Word_Problems/280089: Suppose that the length of a rectangle is three cm longer than twice the width and that the perimeter of the rectangle is 90 cm. Set up an equation for the perimeter involving only w, the width of the rectangle. Solve this equation algebraicially to find the length of the rectangle. Find the width as well. 1 solutions Answer 203565 by rfer(12729)   on 2010-03-12 11:45:52 (Show Source): You can put this solution on YOUR website! 2w+2(2w+3)=90

Radicals/279485: how do you simplify the radicals of the square root of 2/3 times the square root of 18/8? please help!! 1 solutions Answer 203183 by rfer(12729)   on 2010-03-10 20:31:26 (Show Source): You can put this solution on YOUR website! 2/3*18/8=36/24=1.5 sq rt of 1.5=1.225

Volume/279506: A cylinder tank has a 20 foot diameter and is 15 feet tall. How amny cubic feet of water cant the tank hold 1 solutions Answer 203181 by rfer(12729)   on 2010-03-10 20:28:41 (Show Source): You can put this solution on YOUR website! v=pir^2h v=3.14*100*15 v=4710 cu ft

Linear_Equations_And_Systems_Word_Problems/279508: The sum of two numbers is 52, and their difference is 6. What are the numbers? 1 solutions Answer 203179 by rfer(12729)   on 2010-03-10 20:26:17 (Show Source): You can put this solution on YOUR website! x+x-6=52 2x=58 x=29 x-6=23

Polynomials-and-rational-expressions/279447: Jaime bought a case of concert T-shirts for $450. She kept two for herself and sold the rest for $560, making a profit of $10 on each shirt. How many shirts were in the case ? 1 solutions Answer 203177 by rfer(12729)   on 2010-03-10 20:24:24 (Show Source): You can put this solution on YOUR website! 13

Triangles/279468: The measure of the second triangle is 21 degrees more than the measure of the first angle. The measure of the third angle is 15 degrees less than the measure of the first angle. Find the meausre of each angle of the triangle. 1 solutions Answer 203175 by rfer(12729)   on 2010-03-10 20:21:09 (Show Source): You can put this solution on YOUR website! x+x+21+x-15=180 3x=174 x=58 degrees x+21=79 degrees x-15=43 degrees

Equations/279450: Find the y intercept of each equation.Graph each equation. 2x+y=4 1 solutions Answer 203174 by rfer(12729)   on 2010-03-10 20:17:15 (Show Source): You can put this solution on YOUR website! y int is when x=0 2x+y=4 2(0)+y=4 (0,4)

Surface-area/279499: what is the surface area of a cube that has sides of a length of 4 cm 1 solutions Answer 203166 by rfer(12729)   on 2010-03-10 20:08:04 (Show Source): You can put this solution on YOUR website! 4*4*6=96 sq cm

Travel_Word_Problems/279310: At 2:00 p.m. two cars start toward each other from towns 240 miles apart. If the rate of one car is 10 mph faster than the other, how fast does each car go if they meet at 5:00 p.m.? If 3x represents the distance that the slower car traveled, then which expression represents the distance the faster car traveled? 1 solutions Answer 203135 by rfer(12729)   on 2010-03-10 17:15:25 (Show Source): You can put this solution on YOUR website! 3(x+10)

Proportions/279317: I need to write this fraction as a percent. 5/11 (to the nearest tenth of a percent). I came up with 45.5%. Is this correct? Please advise. Thank you. 1 solutions Answer 203134 by rfer(12729)   on 2010-03-10 17:12:26 (Show Source): You can put this solution on YOUR website! looks good to me. Bob

Numeric_Fractions/279380: If you tripe a number you will have one-half the number of hours in two days. What is the number? 1 solutions Answer 203132 by rfer(12729)   on 2010-03-10 17:08:45 (Show Source): You can put this solution on YOUR website! 8

Circles/279341: If the circumference is 7.065 cm then what is the diameter and radius 1 solutions Answer 203131 by rfer(12729)   on 2010-03-10 17:07:55 (Show Source): You can put this solution on YOUR website! 7.065/3.14=2.25 cm diameter 1.125 cm radius