Question
Solving with Elimination Quick Check
3 of 53 of 5 Items
Question
Solve the system of two equations using elimination with multiplication.
4x−6y=−48
−2x+4y=30
(1 point)
Responses
(−33,−9)
left parenthesis negative 33 comma negative 9 right parenthesis
(−3, 6)
left parenthesis negative 3 comma 6 right parenthesis
(−21,−6)
left parenthesis negative 21 comma negative 6 right parenthesis
(3, 9)
Answers
GPT-4o mini
To solve the system of equations using elimination, we'll manipulate the equations to eliminate one of the variables. The given equations are:
1) \(4x - 6y = -48\)
2) \(-2x + 4y = 30\)
First, we can multiply the second equation by 2 to make the coefficients of \(x\) in both equations match:
Multiplying the second equation by 2 gives:
\[
-4x + 8y = 60
\]
Now we rewrite the system of equations:
1) \(4x - 6y = -48\)
2) \(-4x + 8y = 60\)
Next, we add the two equations together to eliminate \(x\):
\[
(4x - 6y) + (-4x + 8y) = -48 + 60
\]
This simplifies to:
\[
0x + 2y = 12
\]
This means:
\[
2y = 12
\]
Dividing both sides by 2 gives us:
\[
y = 6
\]
Now that we have \(y\), we can substitute this value back into one of the original equations to find \(x\). We'll use the first equation:
\[
4x - 6(6) = -48
\]
This simplifies to:
\[
4x - 36 = -48
\]
Adding 36 to both sides:
\[
4x = -48 + 36
\]
\[
4x = -12
\]
Dividing both sides by 4 gives:
\[
x = -3
\]
Thus, the solution to the system of equations is:
\((-3, 6)\)
So the correct response is:
**(−3, 6)**
1) \(4x - 6y = -48\)
2) \(-2x + 4y = 30\)
First, we can multiply the second equation by 2 to make the coefficients of \(x\) in both equations match:
Multiplying the second equation by 2 gives:
\[
-4x + 8y = 60
\]
Now we rewrite the system of equations:
1) \(4x - 6y = -48\)
2) \(-4x + 8y = 60\)
Next, we add the two equations together to eliminate \(x\):
\[
(4x - 6y) + (-4x + 8y) = -48 + 60
\]
This simplifies to:
\[
0x + 2y = 12
\]
This means:
\[
2y = 12
\]
Dividing both sides by 2 gives us:
\[
y = 6
\]
Now that we have \(y\), we can substitute this value back into one of the original equations to find \(x\). We'll use the first equation:
\[
4x - 6(6) = -48
\]
This simplifies to:
\[
4x - 36 = -48
\]
Adding 36 to both sides:
\[
4x = -48 + 36
\]
\[
4x = -12
\]
Dividing both sides by 4 gives:
\[
x = -3
\]
Thus, the solution to the system of equations is:
\((-3, 6)\)
So the correct response is:
**(−3, 6)**