SOLUTION: Given the system of equations.
4x+y=8
6x-9y=12
Which of the options represents the resulting equation after an equivalent expression for y is substituted into the second equatio
Algebra.Com
Question 1090552: Given the system of equations.
4x+y=8
6x-9y=12
Which of the options represents the resulting equation after an equivalent expression for y is substituted into the second equation?
6x - 9(4x - 8) = 12
4x + 4x - 8 = 8
6(4x - 8) - 9y = 12
6x - 9(-4x + 8) = 12
I also do not understand how to find this, so any help would be nice on that subject
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Start with the first equation 4x+y=8.
Isolate y. In other words, get y all by itself on its own side. We do this by subtracting 4x from both sides
4x+y=8
4x+y-4x=8-4x
y=8-4x
y=-4x+8
------------------------------------------------------
The equation y=-4x+8 basically says that y is the same as -4x+8. Because of this, we can replace every 'y' in the second equation with '-4x+8'
6x-9y=12
6x-9( y )=12
6x-9( y )=12
6x-9( -4x+8 )=12 ... note how the terms in blue indicate how the replacement is happening
So the answer is choice D
RELATED QUESTIONS
Write a matrix equation equivalent to the system of equations.
9x + 9y = -9
5x - 2y = 6
(answered by venugopalramana)
solve the following system of equations
6x+7y=4... (answered by LinnW)
Solve the system of equations using substitution
y=6x, y=4x+12
Graph each equation... (answered by josgarithmetic)
Find the values of x and y that solve the following system of equations.
-7x+9y=-12... (answered by tran3209)
Which of these images represents the following system of equations being solved... (answered by mananth)
Keir replaces the second equation in the system below with the second equation plus the 3 (answered by stanbon)
Which of these images represents the following system of equations being solved... (answered by richwmiller)
Which of these images represents the following system of equations being solved... (answered by ankor@dixie-net.com)
What is the solution of the system
9y-6x=12... (answered by checkley77)