Questions on Algebra: Equations answered by real tutors!

Tutors Answer Your Questions about Equations (FREE)

Question 772395: Please help me to solve this equation/problem: 21-y=2y
I know that y=7 but my teacher said I have to show working and I don't know how to do this.

Click here to see answer by josgarithmetic(39616)

Question 772400: How do you factorise: (k+m)-n(k+m)?
Thank you so much.

Click here to see answer by Tatiana_Stebko(1539)

Question 772438: can someone help me with this subsutuion method problem please
Solve this system by elimination:
6x + 2y = 52
3x = 14 + 5y
x of solution (nearest integer):
y of solution (nearest integer):
Click here to see answer by Cromlix(4381)

Question 772439: Dear Sir/Madam,
A pleasant day to you! Can you please help me with this problem, I do have answers to the questions but I am not sure of them, please help me. Thank you very much!
Given the vertices of a triangle A(4,4) B(-6,2) C(-8,10).
a)Find the equation of the medians.
b) show that the medians intersect at one point
c) find the equation of the perpendicular bisectors.
Again, thank you very much for your help!
Click here to see answer by solver91311(24713)

Question 772462: Two years ago, my age was four times that of my son. Eight years ago, my age was ten times that of my son. Find the age of my son now.
Click here to see answer by josmiceli(19441)

Question 772499: What is the slope of the line joining (-4,7) and (-5,0)
Click here to see answer by solver91311(24713)

Question 772500: How far is the point (-3,-4) from the origin?
Click here to see answer by solver91311(24713)

Question 772495: Find the equation of the line that passes through (2,-3) and is perpendicular to the line 2x-y=10
Click here to see answer by lwsshak3(11628)

Question 772497: What is the slope of a line parallel to the line whose equation is y=-�x+3
Click here to see answer by MathLover1(20849)

Question 772498: Find the y-intercept and the slope for �y=x+4
Click here to see answer by MathLover1(20849)

Question 772387: When Katy was 12, her father was three times her age. Now he is twice her age. How old is Katy now?
Click here to see answer by Edwin McCravy(20054)

Question 772514: d=1/2at^2 How do I solve for "t"?
thanks
Click here to see answer by solver91311(24713)

Question 772529: What's the value of (10-5)^2 + 12/4?
Click here to see answer by rfer(16322)

Question 772535: Y=2x/a+2b solve for a?

Click here to see answer by rfer(16322)

Question 772540: A=p+prt solve for p?
Click here to see answer by solver91311(24713)

Question 772512: Find all numbers for which the rational expression is not defined.
4/(x-6)

Click here to see answer by tommyt3rd(5050)

Question 772642: Please help. Stuck not sure where to start working this problem out?
3 + -3^2 + 9 -4x when x=1
Click here to see answer by stanbon(75887)

Question 769653: The difference between the age of Sarah and Anna is 15 .What is the sum of their age if Sarah's age is twice Anna's age. Answer in Algebra Form
Click here to see answer by tommyt3rd(5050)

Question 772699: A river flows at 2 m/s. What is the speed through the water of the boat that can go twice as fast downstream as upstream?
Click here to see answer by josmiceli(19441)

Question 772698: The length of a conference room is one and half times its width. A carpet that is twice as long as it is wide is placed on the centre of the room, leaving a 3 m wide border round the carpet. Find the area of the carpet.
Click here to see answer by josgarithmetic(39616)

Question 772682: LINE PERPENDICULAR TO -4X+Y=-25 AND CONTAINS (4,-10)
Click here to see answer by Cromlix(4381)

Question 772775: 5(x + 4) = 3(8 - x)

Click here to see answer by pakhi(24)

Question 772675: A group of 30 tourists paid a total of $686 in bus fares. If the adult fare was $28 and children paid half fare, how many adults were in the group?
Click here to see answer by pakhi(24)

Question 772794: Find all solutions, real and imaginary, of the equation: 4t^4 - 13t^2 = 12
Click here to see answer by htmentor(1343)

Question 772794: Find all solutions, real and imaginary, of the equation: 4t^4 - 13t^2 = 12
Click here to see answer by lwsshak3(11628)

Question 772851: Please help me get the correct answer to this equation. Here is the problem: 0.7(3x+6)=1.1-(x-2). I got an answer of 11/33 but that is not the correct answer. In the back of my textbook it has an answer of -51/31. Here is what I worked out.
10(2.1x+4.2)=10(1.1-1x+2)
10(2.1x+4.2)=10(3.1-1x)
(10)*2.1x + (10)*4.2 = (10)*3.1 -(10)*1x
21x+42=31-10x
21x+10x=31-42
31x=-11
31x/31=-11/31
My Answer: -11/31
Your help will be greatly appreciated.

Click here to see answer by Alan3354(69443)

Question 772855: 2/3x + 4 4/45 greater than 10 3/10
Click here to see answer by stanbon(75887)

Question 772899: 10=x/4-8
Click here to see answer by oscargut(2103)

Question 772861: put this linear equation into slope intercept form:
x+2(x-5)/10 -2y = 3/4y-(4-3y)+x
Click here to see answer by josgarithmetic(39616)

Question 772958: I am very unsure how to do equation of a straight line? I find all the letters and numbers really confusing and i do not understand where half the numbers come from.for example: point (-2,7), gradient=1/2. it says the answer is y-7=1/2 (x-(-2)), x=2y=16=0. where does the 16 come from?
Click here to see answer by josgarithmetic(39616)

Question 772980: Find an equation of the line that passes through the given point and has the given slope. Express your answer in slope-intercept form.
(8, 0), m = -3

Click here to see answer by mananth(16946)

Question 772981: Find an equation of the line that passes through the given point and has the given slope. Express your answer in slope-intercept form.
(8, 0), m = -3

Click here to see answer by jim_thompson5910(35256)

Question 773132: (X+14 )(x+13)=?
Click here to see answer by Tatiana_Stebko(1539)

Question 773155: how do you get the answer for this equation
6x-10+-3x+8
Click here to see answer by josmiceli(19441)

Question 773191: 4/8+(-1/8)=

Click here to see answer by MathLover1(20849)

Question 773288: solve for the variable
1/3(x-2)=x/4+2
Click here to see answer by tommyt3rd(5050)

Question 773258: I really need help with this. I can't figure it out. (6+2x3) divided by (9-7)exponent 2
Click here to see answer by tommyt3rd(5050)

Question 773337: how do i simplify this equation or make the x the subject
6-(3-x)=21-7/2x
the 7/2 is a fraction
Click here to see answer by Alan3354(69443)

Question 773338: Find the horizontal intercepts of the quadratic equation: 4x2 - 15x - 4 = 0.

Click here to see answer by Cromlix(4381)

Question 773224: the width of a rectangle is 8 inches more than the length. The perimeter is 32. find the length and width of the rectangle.
Click here to see answer by Cromlix(4381)

Question 772448: Solve for:
Click here to see answer by Edwin McCravy(20054)

Question 773371: How would you solve the following system by elimination:
11x - 10y = -18
x - 7y = -26
Thank you.

Click here to see answer by b_souj(3)

Question 773414: Hello, can you show me how to process the following equation: -4 + 5 - (-12) =
Click here to see answer by stanbon(75887)

Question 772995: i have five boxes of counters and eight counters left over.
There are 68 counters altogether. How many are in each full box?
Click here to see answer by tommyt3rd(5050)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 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39916..39960, 39961..40005, 40006..40050, 40051..40095, 40096..40140, 40141..40185, 40186..40230, 40231..40275, 40276..40320, 40321..40365, 40366..40410, 40411..40455, 40456..40500, 40501..40545, 40546..40590, 40591..40635, 40636..40680, 40681..40725, 40726..40770, 40771..40815, 40816..40860, 40861..40905, 40906..40950, 40951..40995, 40996..41040, 41041..41085, 41086..41130, 41131..41175, 41176..41220, 41221..41265, 41266..41310, 41311..41355, 41356..41400, 41401..41445, 41446..41490, 41491..41535, 41536..41580