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

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

Question 198901:
Please solve by the elimination method.
5r-6s = 21
6r+5s = 74
What is the solution of the system? Type an ordered pair.
Thank you.
Click here to see answer by Edwin McCravy(8879)

Question 199075: Hi, thank you for your help,my question is if p= - ak; a=
Click here to see answer by nerdybill(6948)

Question 199204: make K the subject of the formula
[square root of (k-m)]/n=1/m
Click here to see answer by ankor@dixie-net.com(15624)

Question 199250: find the length of the diagonal of a cube with side length 10cm
i don't even know where to start.
Click here to see answer by checkley77(12569)

Question 199364: change 7(x+3) to a sum
Click here to see answer by edjones(7569)

Question 199470: Sorry, this is not out of a book, just a list of practice problems an instructor made up!
Here is the problem:
y=(2x+5)/(5x-7) Solve for x
Click here to see answer by ankor@dixie-net.com(15624)

Question 199591: find A using the formula A=Pe^rt
p=5000
r=6%
t=24
i know you are supposed to plug in the variables and i cannot get the answer 21,103.48 can you explain
Click here to see answer by scott8148(6628)

Question 199780: I'm trying to solve this equation that I translated.
The sum of a number z divided by 3 and the number. = z/3+z
I have the translation down right, but my online homeword from webassign.com is not recognizing 4z/3 as the correct answer. Is my answer wrong?
Click here to see answer by jim_thompson5910(28476)

Question 199722: Can someone please help me with this:
The Acme Class Ring Company designs and sells two types fo rings: the VIP and the SST. They can produce up to 24 rings each day using up to 60 total man-hours of labor. Its takes 3 man-hours to make one VIP ring versus 2 man-hours to make one SST ring.
How many of each type of ring should be made daily to maximize the companys profit, if the profit on a VIP ring is $40 and an SST ring is $35?
a. 14 VIP AND 10 SST
b. 16 VIP AND 8 SST
c. 12 VIP AND 12 SST
Click here to see answer by RAY100(1637)

Question 199798: the number of students on the foot ball team is two more than three times the number of students on the basketball team . if the basketball team has y students how many students are on the football team ?
Click here to see answer by jim_thompson5910(28476)

Question 199968: Let f(x)=x^2-3x and g(x)=2x-4, find and simplify each expression.
g*f
and
f(g(0))
Click here to see answer by jim_thompson5910(28476)

Question 200029: (-8x+5y-12)-6(2x-4y-10)
Click here to see answer by jim_thompson5910(28476)

Question 200063: multiply the following fractions
2/3.5/7
1/3.5/9
7/5.11/6
Click here to see answer by jerrybassmasta(14)

Question 200214: x=-2/5+9
Click here to see answer by rfer(12644)

Question 200349: The equation B=1+3n tells the number of beams required to build a frame of n sections. How many sections can be built with 79 beams?
Click here to see answer by tutorcecilia(2152)

Question 200377: (5/u)-2 = (15/U)+4
Click here to see answer by nerdybill(6948)

Question 200374: Hello,
I need some help. I keep trying the following problem and am not sure what I am doing wrong. I am not sure if I am changing the signs in the right places. The problem and what I have so far are as follows:
Perform the indicated operations:
(x^2 - 4x + 1) - (-8x^2 + 2x - 6) - (x^2 + 3x + 3/5)
x^2 - 8x^2 - x^2 - 4x + 2x + 3x + 1 - 6 + 3/5
Can you please help. Thank you in advance.

Click here to see answer by nerdybill(6948)

Question 200444: i need help on how to write and equation in slope form using (2,-5) with a slope of -5/3 thanks
Click here to see answer by Alan3354(30959)

Question 200547: If Sam and odel were telling pizzas and sam sold half as many pizzas as odel and together they sold 126 pizzas. How many pizzas did sam sell? (That is the question] i tried multipying "x(x/2)=126" but the answer didnt come out right. how would you set this equation up to solve the problem ?
Click here to see answer by edjones(7569)

Question 200726: Linda and dave leave simultaneously from the same directions. Linda bikes at 7 miles per hour and dave bikes at 9 miles per hour. How long will it be until they are 24 miles apart and how do I set the problem up

Click here to see answer by rfer(12644)

Question 200778: 1/4n=10=2/3n
Click here to see answer by Alan3354(30959)

Question 200826: w^2 + 49 = 0
Click here to see answer by RAY100(1637)

Question 200825: b^4 + 13b^2 + 36 = 0
Click here to see answer by RAY100(1637)

Question 200823: Find b^2 - 4ac and the number of real solutions
-3x^2 + 7x = 0
Click here to see answer by RAY100(1637)

Question 200822: PLease help solve
a^2 – 40 = 0
and w^2 + 49 = 0
Click here to see answer by RAY100(1637)

Question 200808: Find a number such that four times two more than the number is the same seven less than the opposite of the number.
Click here to see answer by Earlsdon(6287)

Question 200859: In writing out an answer, for example: m more than nineteen. Will it be the variable first or the number? Is their a rule when putting which first?
Click here to see answer by jim_thompson5910(28476)

Question 200954: Solve by factoring.
z^2 - 3z - 18 = 0
Click here to see answer by solver91311(16868)

Question 200969: please help with step by step 5x^2-125 over x^3+5x^2 multiply 6x^2+2x over 5x-25
Click here to see answer by jim_thompson5910(28476)

Question 200968: please help with step by step 5x^4+2x^3 over 2x^4+3x^3 multiply by 2x^3+x^2-3x over 5x^2-3x-2
Click here to see answer by jim_thompson5910(28476)

Question 201103: Find the vertex and the axis of symmetry of the following parabola.
y = 4x^2 + 24x – 1

Click here to see answer by stanbon(57219)

Question 201102: Solve the following equation by using the quadratic formula:
p2 + 8p + 16 = 0
Find the perfect square trinomial whose first two terms are:
a^2 - 4a.
Determine the vertex and the axis of symmetry of the given quadratic.
y = ¼x^2 - x + 5

Click here to see answer by stanbon(57219)

Question 201101: Find the perfect square trinomial whose first two terms are:
a^2 - 8a
Solve by completing the square.
t^2 - 3t - 7 = 0
An object in launched directly upward at 64 feet per second (ft/s) from a platform 80 feet
high. What will be the object's maximum height? When will it attain this height?

Click here to see answer by Earlsdon(6287)

Question 201119: Can someone please help me with this:
Perform the indicated operation. Give the answer in lowest terms.
3x^2/4 x 16/x^3
Click here to see answer by jim_thompson5910(28476)

Question 201129: 3x + 5y = 44
8x - 7y = -25
Click here to see answer by checkley77(12569)

Question 201185: Can someone please help me with this.
Simplify the expression. Write answer with positive exponents. Variables are positive real numbers.
x^1/3 x^2/3
a. 1/x
b. x
c. x^2/3
d. x^2/9
Click here to see answer by jim_thompson5910(28476)

Question 201304: Find the slope of the line that passes through the points (-9, 2) and (1, 1).
(Reduce your answer.)

Click here to see answer by Earlsdon(6287)

Question 201300: Solve by factoring.
a^2 - 3a - 18 = 0

Click here to see answer by Earlsdon(6287)

Question 201297: solve(x +15)(x-1)(x+13)>0
the solution set is ??
Click here to see answer by rfer(12644)

Question 201358: I'm not quite sure if this is the right section, but here's the problem I need help with. It's on a practice test for the SAT II Subject Test in Math Level IC:
9. If 4x - 7 = 6z + w, then what does the expression 12 - 4x + y equal in terms of z and w?
I tried manipulating the given equations but I couldn't get far.
Here are the answer choices:
A. 12-w
B. 12-6z
C. 12+6z+w
D. 12-6z+w
E. 12-6z-w
Thanks so much for any help!
Click here to see answer by jsmallt9(3296)

Question 200967: please help with step by step 3x^2-6x over x^3+2x^2 divided by -x^2-2x+8 over x^4+6x^3+8x^2
Click here to see answer by jsmallt9(3296)

Question 201422: Please help me solve this problem:
x=1/8y-1
y=1/4x+3
Click here to see answer by stanbon(57219)

Question 201421: Please help me solve this problem:
y=1/2x-3
y=1/3x+2
I tried this
y=1/3x+2
-1/3x+y=2
-y=-y
-1/3x =-y+2
3/1(-1/3x)=(-y+2)3/1
x=-3y+6
Then substitue x=-3y+6
y=1/x(-3y+6)-3
y=-3/xy+6/2-3
y=-3/2y+3-3

But now I am lost
Click here to see answer by stanbon(57219)

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