Questions on Algebra: Linear Algebra (NOT Linear Equations) answered by real tutors!

Tutors Answer Your Questions about Linear Algebra (FREE)

Question 101084: Solve for the variable indicated

W=4r-3R solve for "R"
Click here to see answer by stanbon(75887)

Question 101689: I am lost about where to put the data on these functions Please help. The question is;
The owners of a landscaping company have determined that their weekly revenue and cost in dollars are given by:
R(x)= 95x and C(x)= 45x + 2,000 where x is the number od lawns serviced.
a. What will revenue and cost be if they service 30 lawns?
b. How many lawns must they service in order to reach their break-even point?
Thank you for your time
Click here to see answer by stanbon(75887)

Question 101717: I cant seem to figure out what to do with the data given.
Bob owns a watch repair shop. He is open 5 days per week. Over the years, he has determined that the weekly cost in dollars (in dollars) of operating his shop is given by the cost function: C(x)= 2x^2-57x+26 where x is the number of watches repaired.
What is the daily cost of running the shop if the number of watches repaired is 50?
Thank you for your help
Click here to see answer by stanbon(75887)

Question 101691: can you help:
you are starting a business selling boxes of hand-painted greeting cards. to get started, you spend $36 on paint and paintbrushes that you need. Yoou buy boxes of plain cards for $3.50 per box, paint the cards, and then sell them for $5 per box. how many boxes must you sell for your revenue to equal your expenses? What will your revenue and expenses equal when you break even?
HELP ME PLUEEZE
Click here to see answer by ankor@dixie-net.com(22740)

Question 101682: I am lost about where to put the data. Please help. The question is;
Let the supply and demand functions for sweaters in dollars be:
supply: p=9q+6
demand: p=76-5q
a. Find the equilibrium demand.
b. Find the equilibrium price.
Thank you for your time
Click here to see answer by ankor@dixie-net.com(22740)

Question 101865: if 2 is subtracted from a number and this difference is tripled, the result is 6 more than the number.Find the number.
Click here to see answer by stanbon(75887)

Question 101865: if 2 is subtracted from a number and this difference is tripled, the result is 6 more than the number.Find the number.
Click here to see answer by edjones(8007)

Question 101868: In one day, a store sold 8/5 as many DVDs as CDs. The total number of DVD's and CDs sold that day wa 273. How many DVDs were sold.
Click here to see answer by Kalmetam(43)

Question 101815: Still having a little trouble with functions. Question is:
Let the supply and demand function for sweaters in dollars be;
supply: p=9q+6
demand: p=76-5q
a. Find the equalibrium demand
b. Find the equalibrium price
Thank you for all your help
Click here to see answer by stanbon(75887)

Question 101978: after hours of trying to help my kid i cannot figure this out and nothing i can or have tried works
(x/x*x)+(x*x*x/x)+(x*x)=100 using only 1 - 9
Click here to see answer by stanbon(75887)

Question 101695: I am lost on how find the functions with the information given. Please help. The information given is;
A small family bakery specializes in baking cheesecakes. The fixed cost of production is $245, the marginal cost per cheesecake is $5, and each cheesecake sells for $12. Assume that the cost function is linear.
a. What is the cost function?
b. What is the revenue function?
c. What is the break-even point?
Thank you for your time
Click here to see answer by ankor@dixie-net.com(22740)

Question 102267: Multiplication of matrices are only commutative for some cases of matrices. What are these cases?
Click here to see answer by jim_thompson5910(35256)

Question 100306: A rectangle has an area of X^3 � 6X^2 + 15X � 28 square feet. Its width is X � 4 feet.
What is its length?
Click here to see answer by edjones(8007)

Question 102778: Find an equatioin in standard form of the line having slope m and y-intercept b
m = 1/2, b = 3/2
Click here to see answer by stanbon(75887)

Question 102835: find an equation in standard form of the line containing the given points.
(3,-2), (-2,3)
Click here to see answer by checkley75(3666)

Question 103055: find an equation in standard form of the line having slope m and y-intercept b
m = -1, b = 2
Click here to see answer by doukungfoo(195)

Question 103046: find an equation in standard form of the line containg point P and having slope m P(-3,-2),m=1/2
Click here to see answer by elima(1433)

Question 103054: find an equation in standard form of the ine containing the give points
(0,0),(5,-2)
Click here to see answer by elima(1433)

Question 103681: what is the answer for ...
v = r + at ,for a
Click here to see answer by stanbon(75887)

Question 103754: Baking a try of corn muffins takes 4 c milk and 3 c wheat flour. A tray of bran muffins takes 2 c milk and 3 c wheat flour. A baker has 16 c milk and 15 c wheat flour. He makes $3 profit per tray of corn muffins and $2 profit per tray of bran muffins. How many trays of each type of muffin should the baker make to maximize his profit?
Click here to see answer by stanbon(75887)

Question 103895: (3x^2+4x-7)/(x-2)
Click here to see answer by Nate(3500)

Question 103895: (3x^2+4x-7)/(x-2)
Click here to see answer by checkley75(3666)

Question 103908: I need to factor this problem.
8x^3y^2 - 18xy^4
Click here to see answer by jim_thompson5910(35256)

Question 103908: I need to factor this problem.
8x^3y^2 - 18xy^4
Click here to see answer by stanbon(75887)

Question 103918: I need to factor this problem.
2x+4+xy+2y
Click here to see answer by checkley75(3666)

Question 103860: if f(x)=2x*2-3x+4, find 1-f(0) 2-f(1) 3-f(2) 4-f(-2) 5-f(1/2)
Click here to see answer by checkley75(3666)

Question 105005: Solve the system using any algebraic method:
7x+5y=-12
3x-4y=1
Click here to see answer by elima(1433)

Question 105115: ((x(x-1)) / (x^2+x-6)) <= 0
Click here to see answer by MathLover1(20849)

Question 105114: x^3-4x <= 0
Click here to see answer by MathLover1(20849)

Question 105059: A change machine contains nickels, dimes, and quarters. There are 75 coins in the machine, and the value of the coins is $7.25. There are 5 times as many nickels as dimes. Find the number of coins of each type in the machine.
Click here to see answer by ankor@dixie-net.com(22740)

Question 105113: x^2-6X > 0
Click here to see answer by elima(1433)

Question 105057: 45,500A company placed $1,000,000 in three different accounts. It placed part in short-term notes paying 4.5% per year, twice as much in government bonds paying 5%, and the rest in utility bonds paying 4%. The income after one year was $45,500. How much did the company place in each account?
Click here to see answer by checkley75(3666)

Question 105687: h=5 i=5
(4h-i)^2
Click here to see answer by tutorcecilia(2152)

Question 105860: ok so this is my equation.
and i get it and all its just i cant get it to work
but the teacher told us that i had to be in whole answers
-2x+y+z=-2
5x+3y+3z=71
4x-2y-3z=1
this is what i have tried so far..

5x+3y+3z=71
4x-2y-3z=1
-----------
9x+y=72
and then from there i have tried them all, and it just wont come out.!
please help me.!

Click here to see answer by scott8148(6628)

Question 106052: Write the equation of the line passing through each of the given pairs of points. Write your result in slope-intercept form, where possible. Points: (2,-3) and (2,4) Thanks....again!
Click here to see answer by MathLover1(20849)

Question 106047: Find the slope of any line perpendicular to the line though points (0,5) and (-3,-4) Thank you
Click here to see answer by Fombitz(32388)

Question 106210: You worked 14 hours last week and earned a total of $96.00 before taxes. Your job as a lifeguard pays $8.00 per hour, and your job as a cashier pays $6.00 per hour. How many hours did you work at each job?

I have a problem similar to the above. But can't remember how to set up the solution. My guess is 8x + 6y = 96
Click here to see answer by bucky(2189)

Question 106606: Here is one of the hardest problems I have even seen! Can you please see if you can help with this one? I feel like I can write some functions, but I am really confused.
Product x: Each item sold produces $100 profit
Labor cost: is 3 hours for assembly, 1 hour in detail work, and 2 hours for QA & packing product.
Product y: Each item sold produces $150 profit
Labor cost: is 5 hours for assembly, 3 hour in detail work, and 2 hours for QA & packing product.
Company has these hours available for production for each accounting period:
3900 hours for assembly, 2100 hours for detail work, & 2200 hours for QA & packing.
Questions are:
1) How many products of both x & y should be produced to make a max & min profit?
2) Now what if product y profit goes up to $170 each. How many products are needed to make a max & min profit?
I know this is not an easy question, but do you think you could help with this question please? Thank you kindly.

Click here to see answer by stanbon(75887)

Question 106669: 6x + 4(3x � 2) = 6x + 2
I am getting x=10 but I was not sure if I did it right.
Click here to see answer by rcmcc(152)

Question 106669: 6x + 4(3x � 2) = 6x + 2
I am getting x=10 but I was not sure if I did it right.
Click here to see answer by Earlsdon(6294)

Question 107040: i need help solving these quadratic equations using the quadratic formula.
2x^2 - 5x = 3
3x^2 - 2x + 1 = 0

Click here to see answer by bucky(2189)

Question 107041: i need help solving these quadratic equations using the quadratic formula.
2x^2 - 5x = 3
3x^2 - 2x + 1 = 0

Click here to see answer by HyperBrain(694)

Question 107039: i need help solving these quadratic equations using the quadratic formula.
2x^2 - 5x = 3
3x^2 - 2x + 1 = 0
Click here to see answer by josmiceli(19441)

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