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Question 977078: Find all the solutions to the equation 5x2 + 3x -1 = 7.
I put in 1 for x and got 5(1)^2 + 3(1) - 1 actually equal to 7, but it says find all solutions and I believe there's another solution.
Click here to see answer by ankor@dixie-net.com(22740)

Question 977076: Find the number of pairs of natural number a and b which satisfy 1/a + 2/b = 1/18 where b is an odd natural number less than 80 ??
Click here to see answer by ankor@dixie-net.com(22740)

Question 977207: m-2n=16, 4m+n=1
Click here to see answer by MathLover1(20850)

Question 977208: Oh nuts! Sell pistachio kernels for $10.00 per pound and almonds for $8.00 per pound. How much of each type should be used to make a 50-lb mixture that sells for $8.80 per pound?
Click here to see answer by josgarithmetic(39617)

Question 977294: I have solved the Lowest Common Factor for 36 and 54. LCM = 108
How do I set up a linear function for this?
Click here to see answer by Alan3354(69443)

Question 977333: Find an equation for the line perpendicular to the line 8x+3y= -2 having the same y-intercept as -8x+4y=2.
thank you:)
Click here to see answer by lwsshak3(11628)

Question 977272: Using the following system of inequalities find the maximum value of f(x,y) = 3x + 1y
x≥0
y≥0
3x+2y≤18
6x+7y≤42
Click here to see answer by Fombitz(32388)

Question 977547: Solve this system. Write the answer as an ordered pair.
16x - 10y = 10
-8x - 6y = 6
Click here to see answer by Fombitz(32388)

Question 977642: Write a system of equations to solve the following problem: Mrs. Wright bought 7 containers of cleaning fluid. One of the fluids cost $30 a container and the other was $20 a container. The total price of the supplies was $160. How much of each fluid did Mrs. Wright buy?
Click here to see answer by solver91311(24713)

Question 977807: 5x-10y=90 Solve for y?
Click here to see answer by Edwin McCravy(20056)

Question 977943: The sum of the digits of a certain two-digit number is 8. Reversing its digits decreases the number by 36. What is the number?
A plane traveled 720 miles to Tokyo and back. The trip there was with the wind. It took 6 hours. The trip back was into the wind. The trip back took 12 hours. Find the speed of the plane in still air and the speed of the wind.
Click here to see answer by Boreal(15235)

Question 977990: 2x + Y = 6
x-Y=3
Click here to see answer by stanbon(75887)

Question 978166: The numbers x and y satisfy the equations x(y+2)=100 and y(x+2)=60. What is the value of x - y? Please explain why you say so.
Click here to see answer by josgarithmetic(39617)

Question 978141: the line y=2x+7 is parallel to the line y=2x-3.The line y= -0.5x+7 is perpendicular to the line y=2x-3. Find the perpendicular distance between the pair of parallel lines.
Click here to see answer by KMST(5328)

Question 978382: How do I solve and graph this problem?
y=-2x+5
Click here to see answer by MathLover1(20850)

Question 978682: Having trouble understanding homework and need some step by step instruction for the following equation: 5x^2√(50xv^2) - v√(32x^5). The text does not provide an example for this type of equation. Thank you.
Click here to see answer by Alan3354(69443)

Question 979006: What is 7x+6y=17 ?
Click here to see answer by Fombitz(32388)

Question 979080: Sandy's age is three times Tom's age. Four years from now, Sandy will be twice as old as Tom. How old is Sandy now?
Click here to see answer by josmiceli(19441)

Question 979191: A number consists of two digits whose sum is 8. If 18 is added to the number its digit are reversed. Find the number.
Click here to see answer by anand429(138)

Question 979301: y=-3x+4
y=2x-6
Click here to see answer by Timnewman(323)

Question 979300: d+r=13
1.11r+0.95d=13.15
Click here to see answer by Alan3354(69443)

Question 979387: How many solutions does the system 3x-y=-6 & 3x+y=6 have?
Click here to see answer by jim_thompson5910(35256)

Question 979533: Please help me solve this equation:2x + 2y = -5
Click here to see answer by josmiceli(19441)

Question 979708: Which equation can replace 3x + 5y = 59 in the original system and still produce the same solution?
Click here to see answer by Fombitz(32388)

Question 979773: are the line (-20,5)and (-4,7) and the line through (5,-5) and (7,4) parallel, perpendicular or neither?
Click here to see answer by Alan3354(69443)

Question 979818: The bank only stated the total number of certificates sold (125) and the total generated ($12,660). The bank manager needs to know the number of 6 month CODs purchased and the number of 12 month CODs purchased. 6 month CODs are $112 and 12 month CODs are $92. Write and solve a system of linear equations to determine how many of each type of certificate of deposits were sold.
Click here to see answer by Boreal(15235)

Question 979926: x-z-7
3x-y=1
x+y+z =18
Click here to see answer by Alan3354(69443)

Question 980173: There was a question about an army travelling 5 mph and a messenger on horseback travelling at 10 mph(question asks for the distance from front to rear) that was answered by ankor@dixie.net that I didn't really understand why did he add and subtract 5 to the 10 mph rate. I know that you do add +-r or a given amount in wind and water current problems. Is that why you added and subtracted the 5? Some logic of why is all I need, so that I can understand a problem that I've never seen before in any other place than the Schaum College Algebra textbook. Please help. QUESTION: WHY WAS THE 5 ADDED AND SUBTRACTED FROM 10 TO GET 15 AND 5(Denominators) AND WHY 5 AND NOT R? Anybody that understands fully why and can explain is welcome.
Click here to see answer by josmiceli(19441)

Question 980348: what is the least number of coins required to pay exactly the two items,orange at 7.50 and orange juice at 15.00

Click here to see answer by Alan3354(69443)

Question 980505: 1-y+4=6
Click here to see answer by macston(5194)

Question 980561: The population of a Midwest industrial town decreased from 221,000 to 217,000 in just 5 years. Assuming that this trend continues, what will the population be after an additional 4 years? i need to round to the nearest whole number can anyone please help me

Click here to see answer by josgarithmetic(39617)

Question 980551: What table of values could be generated by the equation 10x+5y=15
Click here to see answer by Alan3354(69443)

Question 980565: In 1995, 500 runners entered a marathon. In 1998, 20500 runners entered the race. Because of the limited number of facilities, the carrying capacity of the number of racers is 58500. The number of racers at any time, t, in years, can be modeled by the logistic function of p(t)=c/1+Be^kt
1. what is the value of c? 58500
2. what is the value of b? 116
3. what is the value of k? 1/3 ln 19/1189
4. in what year should at least 50500 runners be expected to run in the race?
i was able to solve for the above but i need help solving for the last part #4. thank you so much
Click here to see answer by Boreal(15235)

Question 980603: Solve the system of linear equations by graphing
3x+y=9
6x=2y+6
Click here to see answer by MathLover1(20850)

Question 980625: Grade 9 maths 'please help me solve this equation 3x-4=x+2
Click here to see answer by josgarithmetic(39617)

Question 980643: "solve the exponential equation: (3.51)^-2x/15=8
i keep getting an undefined answer. thanks for the help
Click here to see answer by Cromlix(4381)

Question 980758: Hey my name is Andrea I need help with linear equations here is my problem :
(3, -1) is the midpoint between (-2, -7) and what other point ?
Click here to see answer by Alan3354(69443)

Question 980768: Hey my name is Andrea and I have a more question I need help with :
Write the equation of a line in point slope form that goes through (2, -4) and (-1, 0). Then convert into slope intercept form.
Click here to see answer by josgarithmetic(39617)

Question 980789: 2(1-y) thank you
Click here to see answer by Alan3354(69443)

Question 980959: Mark deposited $9,000 into two saving accounts bearing simple interest. One of the accounts has an interest rate of 8% while the other rate is 7%. If the total interest earned after one year is $700, find the amount deposited into each of the accounts
Click here to see answer by macston(5194)

Question 980980: It takes 8 hours for car A to travel 500 km. How many hours will car B travel 500 km if its speed is 50 less than twice the average speed of car A?
Click here to see answer by macston(5194)

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