# Questions on Algebra: Expressions involving variables, substitution answered by real tutors!

Algebra ->  Algebra  -> Expressions-with-variables -> Questions on Algebra: Expressions involving variables, substitution answered by real tutors!      Log On

 Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help! Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!

 Algebra: Expressions involving variables, substitution Solvers Lessons Answers archive Quiz In Depth

 Question 328946: Simplify (-4 + x^2 + 2x^3) – (-6 – x + 3x^3) – (-6y^3 + y^2) Click here to see answer by checkley77(12569)

 Question 329392: Show me how to use elimination to solve the system of equations given by 3x-2y=10 and 5x+2y=6. Thanks Click here to see answer by Tutorteddy.Com(12)
 Question 329392: Show me how to use elimination to solve the system of equations given by 3x-2y=10 and 5x+2y=6. Thanks Click here to see answer by Edwin McCravy(8906)

 Question 329612: The following appears to prove that any two numbers are equal. Obviously it is wrong; can you spot the flaw? Let a and b be any two different numbers. Define x as the difference between them: x = b - a Multiply both sides of the equation by (b-a): x(b – a) = (b – a)(b – a) bx – ax = b2 – 2ab + a2 Add –bx+ab-a2 to both sides and simplify: bx – ax – bx + ab – a2 = b2 – 2ab + a2 – bx + ab – a2 bx – bx – ax + ab – a2 = –bx + b2 – 2ab + ab + a2 – a2 –ax + ab – a2 = –bx + b2 – ab Both sides of this equation have a common factor: a(–x + b – a) = b(–x + b – a) Divide both sides by (-x+b-a): a(–x + b – a) = b(–x + b – a) –x + b – a –x + b – a a = b What was my mistake? Click here to see answer by stanbon(57299)
 Question 329612: The following appears to prove that any two numbers are equal. Obviously it is wrong; can you spot the flaw? Let a and b be any two different numbers. Define x as the difference between them: x = b - a Multiply both sides of the equation by (b-a): x(b – a) = (b – a)(b – a) bx – ax = b2 – 2ab + a2 Add –bx+ab-a2 to both sides and simplify: bx – ax – bx + ab – a2 = b2 – 2ab + a2 – bx + ab – a2 bx – bx – ax + ab – a2 = –bx + b2 – 2ab + ab + a2 – a2 –ax + ab – a2 = –bx + b2 – ab Both sides of this equation have a common factor: a(–x + b – a) = b(–x + b – a) Divide both sides by (-x+b-a): a(–x + b – a) = b(–x + b – a) –x + b – a –x + b – a a = b What was my mistake? Click here to see answer by galactus(183)
 Question 329612: The following appears to prove that any two numbers are equal. Obviously it is wrong; can you spot the flaw? Let a and b be any two different numbers. Define x as the difference between them: x = b - a Multiply both sides of the equation by (b-a): x(b – a) = (b – a)(b – a) bx – ax = b2 – 2ab + a2 Add –bx+ab-a2 to both sides and simplify: bx – ax – bx + ab – a2 = b2 – 2ab + a2 – bx + ab – a2 bx – bx – ax + ab – a2 = –bx + b2 – 2ab + ab + a2 – a2 –ax + ab – a2 = –bx + b2 – ab Both sides of this equation have a common factor: a(–x + b – a) = b(–x + b – a) Divide both sides by (-x+b-a): a(–x + b – a) = b(–x + b – a) –x + b – a –x + b – a a = b What was my mistake? Click here to see answer by Theo(3458)

 Question 329731: find all numbers for which the rational expression is undefined. 5/x-2 Click here to see answer by edjones(7569)

 Question 329732: Keiko bicycles 5 km/h faster than Praedup. In the same time it takes praedup to bicycle 54 km, Keiko can bicycle 69 km. How fast does each bicyclist travel? Praedup travels ______ km/h. Keiko travels ________ km/h. Click here to see answer by mananth(12270)

 Question 329727: use the given information to find the constant of variation and the variation equation. y varies jointly as x and z y=96 when x=8 and z=3 Click here to see answer by Alan3354(30993)

 Question 329871: There are two solutions to the equation x^2=x. Show and explain how you would find both of these solutions algebraically Click here to see answer by Alan3354(30993)

 Question 329986: A rectangle has a width of 12 feet. If its perimeter is 100 feet, what is its length? Shelley E. Click here to see answer by jim_thompson5910(28550)

 Question 329940: Solve 4-x+3=75 The solution is x = ___________ (simplify your answer. Type an integer or a decimal. Round to four decimal places as needed) Click here to see answer by checkley77(12569)

 Question 329983: For the first six years, the loan value of a Corvette is determined by the formula V=-4000a + 50000, where V is the value and a is the age of the car in years. What was its original value? What is its value when it is 5 years old? Thank you, Shelley E. Click here to see answer by edjones(7569)

 Question 329985: You put \$4,750 into a bank paying 1.4% simple interest per year. Suppose you don't take anything out of the account. How much do you have after two years? Thank you, Shelley Click here to see answer by nerdybill(6958)

 Question 330065: find the value of w(w+10) given that 2w+5=15 Click here to see answer by mananth(12270)

 Question 330283: I need to know how to solve an equation for y when there are two y's. The equation is 3xy+y=15. Click here to see answer by Alan3354(30993)

 Question 330355: What is the varible expression for three increased by twice h? Click here to see answer by Fombitz(13828)

 Question 330699: Find the following. Assume all variables can represent any real numbers. sqrt(a+4)^2. I came up with two different answers: a+4 and then a^2+8a+16. Is either one correct? If a+4 is, does it have to be in parenthesis or |a+4|? Please advise. Thank you. Click here to see answer by Fombitz(13828)

 Question 329747: Use the Substitution method to solve the system of equations. x + y = -4 x - y = 2 Click here to see answer by Fombitz(13828)

 Question 330937: Judy and Mary started walking toward each other from two different locations. They started at the same time. Judsy walks 2 miles per hour and Mary walks 2.5 miles per hour. By the time Judy reached mid point, they were 3 miles apart. How far apart were they when they started? Click here to see answer by stanbon(57299)

 Question 330939: Imagine a driver with straight parallel sides and no current. Boat a departs side A at the same time as boat b departs side B, both perpendicular to the riverbank, and both at constant (but possibly different) speeds. They pass each other 800 yards from A, proceed to the opposite shore, turn around, and pass again 400 yards from B. How wide is the river? Click here to see answer by galactus(183)

 Question 331098: how do you write an expresion for the number of hours in 5 days Click here to see answer by stanbon(57299)

 Question 331217: Find the third term in the expansion of (2x-3y)^8 Click here to see answer by Edwin McCravy(8906)

 Question 331343: The sum of the quotient of p&14 and the quotient of q&3 Click here to see answer by solver91311(16877)

 Question 331448: the vaule in cents of n nickels what does that mean Click here to see answer by rfer(12657)

 Question 331471: How do you write b + c + twice a? Click here to see answer by mananth(12270)