Question
Use the substitution method to solve the system 2x+3y=4
, −4x−6y=−8
.(1 point)
Responses
no solution
no solution
infinite solutions
infinite solutions
(2−1)
left parenthesis 2 comma negative 1 right parenthesis
(−1,2)
, −4x−6y=−8
.(1 point)
Responses
no solution
no solution
infinite solutions
infinite solutions
(2−1)
left parenthesis 2 comma negative 1 right parenthesis
(−1,2)
Answers
Answered by
GPT-4o mini
To solve the system of equations using the substitution method, we have the equations:
1. \( 2x + 3y = 4 \) (Equation 1)
2. \( -4x - 6y = -8 \) (Equation 2)
First, we can solve Equation 1 for one variable in terms of the other. Let's solve for \( y \):
\[
3y = 4 - 2x
\]
\[
y = \frac{4 - 2x}{3}
\]
Now we will substitute this expression for \( y \) into Equation 2:
\[
-4x - 6\left(\frac{4 - 2x}{3}\right) = -8
\]
Multiplying through by 3 to eliminate the fraction:
\[
-12x - 6(4 - 2x) = -24
\]
\[
-12x - 24 + 12x = -24
\]
Notice that the terms involving \( x \) cancel out:
\[
-24 = -24
\]
This statement is always true, which means that the two equations are dependent. The second equation is a multiple of the first (specifically, it is equivalent to multiplying the first equation by -2):
\[
-2(2x + 3y) = -2(4) \Rightarrow -4x - 6y = -8
\]
Since the equations represent the same line, the system has infinitely many solutions.
Thus, the answer is:
**infinite solutions**
1. \( 2x + 3y = 4 \) (Equation 1)
2. \( -4x - 6y = -8 \) (Equation 2)
First, we can solve Equation 1 for one variable in terms of the other. Let's solve for \( y \):
\[
3y = 4 - 2x
\]
\[
y = \frac{4 - 2x}{3}
\]
Now we will substitute this expression for \( y \) into Equation 2:
\[
-4x - 6\left(\frac{4 - 2x}{3}\right) = -8
\]
Multiplying through by 3 to eliminate the fraction:
\[
-12x - 6(4 - 2x) = -24
\]
\[
-12x - 24 + 12x = -24
\]
Notice that the terms involving \( x \) cancel out:
\[
-24 = -24
\]
This statement is always true, which means that the two equations are dependent. The second equation is a multiple of the first (specifically, it is equivalent to multiplying the first equation by -2):
\[
-2(2x + 3y) = -2(4) \Rightarrow -4x - 6y = -8
\]
Since the equations represent the same line, the system has infinitely many solutions.
Thus, the answer is:
**infinite solutions**