Asked by kymari davis-shanks
Solving Equations Using Substitution Quick Check
3 of 53 of 5 Items
Question
Solve the system of equations.
3x+y=2
7x−4y=30
(1 point)
Responses
(2, −2)
left parenthesis 2 comma negative 2 right parenthesis
(2, −4)
left parenthesis 2 comma negative 4 right parenthesis
(−2, 8)
left parenthesis negative 2 comma 8 right parenthesis
(12, 12)
3 of 53 of 5 Items
Question
Solve the system of equations.
3x+y=2
7x−4y=30
(1 point)
Responses
(2, −2)
left parenthesis 2 comma negative 2 right parenthesis
(2, −4)
left parenthesis 2 comma negative 4 right parenthesis
(−2, 8)
left parenthesis negative 2 comma 8 right parenthesis
(12, 12)
Answers
Answered by
GPT-4o mini
To solve the system of equations using substitution, we have the following equations:
1. \(3x + y = 2\) (Equation 1)
2. \(7x - 4y = 30\) (Equation 2)
Let's solve Equation 1 for \(y\):
\[
y = 2 - 3x
\]
Now we can substitute this expression for \(y\) into Equation 2:
\[
7x - 4(2 - 3x) = 30
\]
Distributing the \(-4\):
\[
7x - 8 + 12x = 30
\]
Combining like terms:
\[
19x - 8 = 30
\]
Adding \(8\) to both sides:
\[
19x = 38
\]
Dividing both sides by \(19\):
\[
x = 2
\]
Now we substitute \(x = 2\) back into the expression for \(y\):
\[
y = 2 - 3(2) = 2 - 6 = -4
\]
Thus, the solution to the system of equations is:
\[
(x, y) = (2, -4)
\]
So the correct response is:
**(2, −4)**
1. \(3x + y = 2\) (Equation 1)
2. \(7x - 4y = 30\) (Equation 2)
Let's solve Equation 1 for \(y\):
\[
y = 2 - 3x
\]
Now we can substitute this expression for \(y\) into Equation 2:
\[
7x - 4(2 - 3x) = 30
\]
Distributing the \(-4\):
\[
7x - 8 + 12x = 30
\]
Combining like terms:
\[
19x - 8 = 30
\]
Adding \(8\) to both sides:
\[
19x = 38
\]
Dividing both sides by \(19\):
\[
x = 2
\]
Now we substitute \(x = 2\) back into the expression for \(y\):
\[
y = 2 - 3(2) = 2 - 6 = -4
\]
Thus, the solution to the system of equations is:
\[
(x, y) = (2, -4)
\]
So the correct response is:
**(2, −4)**