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

Tutors Answer Your Questions about Expressions-with-variables (FREE)

Question 104289: Motorboat Travel. A motorboat traveled for 2 hrs with an 8-km/hr current. The return trip against the same current took 3 hrs. Find the speed of the motorboat in still water.
I have so far but don't know if I am even close
2x + 16 = 3x + -24
2x = 3x + -24 - 16
2x = 3x + -40
-3x + 2x = -40
-x = -40
x = 40
but I not think that is all I am suppose to do.
Thank You Tammy
Click here to see answer by stanbon(57219)

Question 104340: sorry if i keep sending so many problems but i need help on some problems i dont get multi step equations so yeah here are the problems,8x-5=4x+4-2x;15-3y=y+13+y;3w-1-4w=4-2w
Click here to see answer by stanbon(57219)

Question 104435: The problem reads 0.9y-18=0.3y
Step 1 Substract .9y from each side
Step 2 -18=-.6y
Step 3 Divide by -.6
Step 4 Answer is ? I got the answer as 30, but not sur eif I am right.

Click here to see answer by Earlsdon(6287)

Question 104443: What is an 'outlier'
Click here to see answer by Allstar(7)

Question 104291: The octane rating of a gasoline is a measure of the amount of iso-octane in the gas. How much 87-octane gas should be blended in order to end up with 12gal of 91-octane gas?
87x + 93y = 12 x 91
87x + 93y = 1092
87x = -93y + 1092
x = -93y/-87 + 1092/-87
x = 31/29 + 364/29
Click here to see answer by scott8148(6628)

Question 104408: Hello,

I'm having difficulty with this problem:

The distance between (a,4) and (-3,-2) is (sqrt)61. I need help finding the two possible values for a.

Thank you
Click here to see answer by Fombitz(13828)

Question 104508: Hello-
My name is Jessica and I am a tutor too. I could not get these for my student. Please help and explain so I can help him.
Thank you!!

1. 1/p-1/q= 1/f solve for f

2. A= (h(a+b))/2 solve for b
3. V= Q/r1- Q/R2 solve for Q
Click here to see answer by Earlsdon(6287)

Question 104577: Here is another problem!
Jo has 37 coins(all nickles, dimes and quarters) worth $5.50. She has 4 more quarters than nickles. How many dimes does Jo have? I can't figure out what the variable for dimes is.
Thanks!
Click here to see answer by stanbon(57219)

Question 104518: Solve 50q-43=52q-81
Click here to see answer by edjones(7569)

Question 104594: I do not know how to solve this equation
Ex:280=8a
PLEASE SHOW STEPS OF SOLVING EQUATION

Click here to see answer by edjones(7569)

Question 104604: May rides her bike the same distance that Leah walks. May rides her bike 10 km/h faster than Leah walks. If it takes May 1 h and Leah 3 h to travel that distance, how fast does each travel?

Click here to see answer by stanbon(57219)

Question 104519: The question is to solve each system. If there is no solution or if there are infintely many solutions and a system's equations are dependent so state. You have to solve the system in Three Variables but I have no clue how. The question is
x+y+2z=11
x+y+3z=14
x+2y+3z=5

Click here to see answer by ankor@dixie-net.com(15624)

Question 104716: Solve 50q-43=52q-81.
What percent of 74 is 481?
Click here to see answer by jim_thompson5910(28476)

Question 104514: Hello,
I just had this question awnsered, but i am confused.
The question was 1/p-1-q=1/f solve for f
I was told;
1. It will simplify things a bit if we first subtract the fractions on the left side.
and got this:
q-p/pq=1/f

I am confused how you got that! please help!Please show step and tell why.
Thank you

Click here to see answer by duggie(26)

Question 104843: how do you simplify 4-3(4x-6)
Click here to see answer by edjones(7569)

Question 105008: 40=7(1/2)
Click here to see answer by elima(1433)

Question 105092: n x 11 is between 135 and 140
Click here to see answer by kmcruz09(38)

Question 105197: 13x-5=94
Click here to see answer by elima(1433)

Question 105305: simplify 7y + 2 + 5y - 6 -y
Click here to see answer by jim_thompson5910(28476)

Question 105328: I have a question concerning substitution and elimination. Goes like this:
Maria drove from Owen Sound to Ottawa, a distance of 550 km. The trip took 7 h. Maria drove at 70 km/h for part of the trip and at 85 km/h for the remainder of the trip. How far did she drive at 70 km/h?
Can you please answer this detailed for me>?
Click here to see answer by checkley75(3666)

Question 105361: 2n=24
Click here to see answer by an(14)

Question 105440: combine like terms...
6a^2+4a+5+3a^2+7a-2
Click here to see answer by jim_thompson5910(28476)

Question 105557: Hello Tutors, Can one of you kind hearted folks help me out. I can't seem to get this right for some reason.
Q: Assume that all variables are Positive and Multiply;
y^3/8(y^-3/8 + 9y^5/8)??
The answers we are given to choose from are,
1) y+9
2) 1+ 9y OR
3)y^-1 + 9y
And unfortunately, no matter what I do I am doing it wromg because I am not geeting any of these answers. Thank You!
Click here to see answer by Fombitz(13828)

Question 105555: Can someone please help me with this problem??
Simplify the expression; assume that all the variables represent positive numbers.
(625x^4y)^1/4
______________
(16xy^3)3/4
Thank You so much
Click here to see answer by Fombitz(13828)

Question 105595: x+2y=10
3x-y=2
Click here to see answer by askmemath(368)

Question 105527: Slove for x=yz

(a)for the variable y=
(b) for the variable z=
Click here to see answer by elima(1433)

Question 105598: Lois rode her bike to visit a friend. She traveled at 10mi/h. While she was there, it began to rain. Her friend drove her home in a car traveling at 25mi/h. Lois took 1.5h longer to go to her friend's than to return home. How many hours did it take Lois to ride to her friend's house?

Click here to see answer by askmemath(368)

Question 105611: I need help defining one variable in terms of another.
The Length of a rectangle is 8in more then its width the perimeter is 24in what are the length and the width? I dont even know where to begin.
Click here to see answer by MathLover1(6614)

Question 105717: if 4n+2p=16,p equals
Click here to see answer by tutorcecilia(2152)

Question 105765: My son had this problem on a test, can you help?
Carla drove to the mountains, averaging 30 mph. Coming back by the same roads, she averaged 20 mph. The total driving time was 5 hours. How far did she travel one way?
Click here to see answer by kmcruz09(38)

Question 105777: evaluate each function for the value specified
f (x)=x^2-7x+10; find (a) f (0), (b) f (5), and (c) f (-2)
Click here to see answer by kmcruz09(38)

Question 105683: -5-4x=7x-6
Click here to see answer by kmcruz09(38)

Question 105871: 4x+5y=11,y=3x-13 confused on how to solve
Click here to see answer by MathLover1(6614)

Question 105932: Robert is 1/2 as old as his father. Twelve years ago he was 1/3 as old as his father was then. Find their present ages
Click here to see answer by Earlsdon(6287)

Question 106086: If f(x)=5x-1. Find the following f (a-2)
Click here to see answer by Fombitz(13828)

Question 106085: If f(x)=4x-3. Find the following f(-1)
Click here to see answer by stanbon(57219)

Question 106173: The length of a rectangle is 3 Inches more than its width. The perimeter of the rectangle is 30 inches.
Click here to see answer by HyperBrain(694)

Question 106136: Problem solving using chart: Question: The Eiffel tower is 497 ft. taller than the Washington monument. If each of the monuments were 58ft. shorter, the eiffel tower would be twice as tall as the Washington monument. How tall is each?
Click here to see answer by ptaylor(2048)

Question 16718: "the product of 10 and a number p"
Click here to see answer by solver91311(16868)

Question 106366: 5/2t-t=3+3/2t
Click here to see answer by edjones(7569)

Question 106453: Hi, I can't figure out this problem, could you help?

How do you solve for c? thanks.
Click here to see answer by Earlsdon(6287)

Question 106453: Hi, I can't figure out this problem, could you help?

How do you solve for c? thanks.
Click here to see answer by solver91311(16868)

Question 106478: I need to simplify the following expression:
12-p(8-6)+3

Thank you
Click here to see answer by MathLover1(6614)

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