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Question 223968: My son's homework question is:
Find the value(s) of a for which the equation is an identity.
a(2x+3) = 9x + 12 - x
What exactly are they asking him to do here? I don't understand what they are looking for. Should he solve for a, or for x in terms of a?
thanks,
Andrea
Click here to see answer by MathTherapy(10552)

Question 224157: solve by using elimination and substitution method:
3x+4y=6 and 2x+3y=5
Click here to see answer by checkley77(12844)

Question 224262: using substitution or elimination, find x and y
3x+y=1
y=x+9
Click here to see answer by drj(1380)

Question 224194: please help me solve for the indicated letter
c=2d, for d
the solution is d=?
Click here to see answer by rfer(16322)

Question 224324: Solve the following system of equations by any method you wish
X + 2y = 2
2x + 4y = 4

Click here to see answer by rapaljer(4671)

Question 224340: Graph the linear system and tell how many solutions it has. If there is exactly one solution, give the solution
4X-5Y=2
8X+Y=4
Click here to see answer by drj(1380)

Question 224344: Graph the linear system and tell how many solutions it has. If there is exactly one solution, give the solution.
-3X+4Y=-16
-6X=-8Y-32
Click here to see answer by drj(1380)

Question 224423: I have to explain how you know when an equation has Infinitely many solutions?.As well as how you know when they do not have any.
I think it is because in order for an equation to have infinitely many solutions you must have many variables, and if they do not have multiple variables then they would only have one solutions. am I correct in that thinking or am I missing something?

Click here to see answer by rapaljer(4671)

Question 224439: Suppose you need to solve a system of equations in which one equation represents a circle and the other represents a line. How many solutions can your system have?
How many solutions does the following system of equations have?
X^2+y^2=64
x=1
Click here to see answer by Alan3354(69443)

Question 224322: Solve the following system of equations by any method you wish
X + y = 5
X + 2z = 6
Y + 3z = 4

Click here to see answer by ankor@dixie-net.com(22740)

Question 224489: find three consecutive even integers such that twice largest integer exceeds the sum of the sum of the first two by 6.
Click here to see answer by drj(1380)

Question 224608: can some one please solve the problem 5(3x-2)-9(2+4x)-7=0 with workings
Click here to see answer by drj(1380)

Question 224733: how do i Find the midpoint of the line segment from ( -1/4 , 1/2 ) to ( -4 , -3 )?
Click here to see answer by Alan3354(69443)

Question 224733: how do i Find the midpoint of the line segment from ( -1/4 , 1/2 ) to ( -4 , -3 )?
Click here to see answer by drj(1380)

Question 225044: I am trying to help my daughter with her homework and need to know how to solve this equation.... 2k + 6 - K = 17
Click here to see answer by Alan3354(69443)

Question 225044: I am trying to help my daughter with her homework and need to know how to solve this equation.... 2k + 6 - K = 17
Click here to see answer by drj(1380)

Question 224321: Solve the following system of equations by any method you wish
X + 2y = 2
2x + 4y = 4

Click here to see answer by Alan3354(69443)

Question 225174: There are 385 surfers in the Surf City. Two-thirds of the boys are surfers and one-twelfth of the girls are surfers. If there are 2 girls for every boy, then how many boys and how many girls are there in Surf City?
Click here to see answer by jim_thompson5910(35256)

Question 225185: how do i solve these two problams using the elimination method ?
1. 10x+6y =0
-7x+2y =31
for this one i got (9.3, -15.5) but i have a feeling that is wrong
and 2. 3x+4y=-13
5x+6y=-19
for this one i got (-25, 15.5) but again , because the answers i gto are so big and decimals, i think im doing the problems wrong

Click here to see answer by jim_thompson5910(35256)

Question 225331: graph the equation Y=-2x+2
Click here to see answer by LtAurora(115)

Question 225406: How do i plot the following 5 equations?
1.) y= x+2
2.) y=2x-2
3.) y=2x+4
4.) y=1/6+6
5.) y=1/2Xsq-8

Click here to see answer by Alan3354(69443)

Question 225635: I need help on this problem 6v-9/3=v.
Click here to see answer by checkley77(12844)

Question 225656: Systems of Equations
A chemist has two solutions of hydrochloric acid in stock: a 50% solution and an 80% solution. How many of each should she mix to obtain 100 milliliters of a 68% solution?
Click here to see answer by checkley77(12844)

Question 225653: v = r + at
Solve For A
Click here to see answer by checkley77(12844)

Question 225675: v = r + at
Solve For A
Click here to see answer by checkley77(12844)

Question 225957: Solve by method of elimination: 2x +3y =10
-3x+y =18
Click here to see answer by drj(1380)

Question 225910: -3=-4y+1
Click here to see answer by drj(1380)

Question 226098: Directions: Translate each sentence into an equation. Then find four solutions for each equation. Write the solutions as ordered pairs. Graph each equation.
1.) Some number is four more than a second number.
Am I supposed to use y=mxtb or use a normal setup of equations? And when I did try y= 4(2)+b I only got 8. And I didn't know what to do with the two variables. So would I do the slope first? I didn't try that because they don't list four different numbers in the question; but I can't complete y=mxtb without knowing what b is. Thanks for your help!
Click here to see answer by solver91311(24713)

Question 226304: What is the equation for a line that contains the points (0,4) and is parallel to y=2x+3?
Click here to see answer by drj(1380)

Question 226538: Hello, I am trying to help my daughter with her algebra homework, but Im a little rusty myself. I've been able to help her understand a few of the problems but these have stumped the both of us. Help would be greatly appreciated! Thank you!
- Burg family

linear equation by any convenient method
2x + y - 3z = 5
x + y - 3z = 1
x - z = 4

linear equation by method of elimination
9x - 2y = 7
-18x + 4y = -7

linear equation by method of elimination
-3x - y = -3
x + 2y = -4

linear equation by any convenient method
x - 2y = -13
-2x - 2y = -4
Click here to see answer by Alan3354(69443)

Question 226616: i am having a problem with linear equation i need help bad
Click here to see answer by Alan3354(69443)

Question 226632: how do i do 5+2(3+4x)
Click here to see answer by checkley77(12844)

Question 226652: 2/3(x-6)+x=3x-2 wat does x equal please shpw work i dont get it

Click here to see answer by rfer(16322)

Question 226654: three times the largest of three consecutive even integers is twenty-two more than the sum of the other two. Find the integers

Click here to see answer by checkley77(12844)

Question 226708: use the intercepts to graph the equation
x+3y=6
Click here to see answer by drj(1380)

Question 226730: 7(2*2)-2+10
Click here to see answer by rfer(16322)

Question 226871: Can you please help me solve this equation for the variable specified? thank you
9a-2b=c+4a, for a
Click here to see answer by rfer(16322)

Question 227174: f a line passes through the points (-5, -4) and (3, -1), the equation of the line is y + 4 = 3/8(x + _____).
Click here to see answer by user_dude2008(1862)

Question 227278: 4. solve by the substitution method
3x+y=2
x=19-5y

Click here to see answer by drj(1380)

Question 227306: 1. Solve by the elimination method

5r-7s=-3
7r+5s=55

Click here to see answer by drj(1380)

Question 227331: 7H <= 6H-1
Click here to see answer by rapaljer(4671)

Question 227488: Hi can you help me solve this equation by substitution
3b+2a=2
-2b+a=8
Click here to see answer by chibisan(131)

Question 227557: use elimination to solve the system of
7x+23y=12
3x+23y=-8
Click here to see answer by checkley77(12844)

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