Question
Solve the system by substitution.
y=2x^2−3x−1
y=x−3
(1 point)
Responses
(1,−2)
open paren 1 comma negative 2 close paren
(3,0),(5,2)
open paren 3 comma 0 close paren comma open paren 5 comma 2 close paren
(4,1)
open paren 4 comma 1 close paren
no solution
y=2x^2−3x−1
y=x−3
(1 point)
Responses
(1,−2)
open paren 1 comma negative 2 close paren
(3,0),(5,2)
open paren 3 comma 0 close paren comma open paren 5 comma 2 close paren
(4,1)
open paren 4 comma 1 close paren
no solution
Answers
Answered by
GPT-4o mini
To solve the system of equations by substitution, we have:
1) \( y = 2x^2 - 3x - 1 \)
2) \( y = x - 3 \)
Since both equations are set equal to \( y \), we can set them equal to each other:
\[
2x^2 - 3x - 1 = x - 3
\]
Now, let's rearrange this equation to set it to zero:
\[
2x^2 - 3x - 1 - x + 3 = 0
\]
Combining like terms gives us:
\[
2x^2 - 4x + 2 = 0
\]
Now we can simplify this equation by dividing all terms by 2:
\[
x^2 - 2x + 1 = 0
\]
This is a perfect square trinomial:
\[
(x - 1)^2 = 0
\]
So, solving for \( x \), we get:
\[
x - 1 = 0 \implies x = 1
\]
Now we substitute \( x = 1 \) back into one of the original equations to find \( y \). We'll use the second equation:
\[
y = x - 3 \implies y = 1 - 3 = -2
\]
Thus, the solution to the system of equations is:
\[
(1, -2)
\]
Therefore, the answer is:
**(1, −2)**
1) \( y = 2x^2 - 3x - 1 \)
2) \( y = x - 3 \)
Since both equations are set equal to \( y \), we can set them equal to each other:
\[
2x^2 - 3x - 1 = x - 3
\]
Now, let's rearrange this equation to set it to zero:
\[
2x^2 - 3x - 1 - x + 3 = 0
\]
Combining like terms gives us:
\[
2x^2 - 4x + 2 = 0
\]
Now we can simplify this equation by dividing all terms by 2:
\[
x^2 - 2x + 1 = 0
\]
This is a perfect square trinomial:
\[
(x - 1)^2 = 0
\]
So, solving for \( x \), we get:
\[
x - 1 = 0 \implies x = 1
\]
Now we substitute \( x = 1 \) back into one of the original equations to find \( y \). We'll use the second equation:
\[
y = x - 3 \implies y = 1 - 3 = -2
\]
Thus, the solution to the system of equations is:
\[
(1, -2)
\]
Therefore, the answer is:
**(1, −2)**