Use the substitution method to solve the system y=−2x+1

, −4x=−2y+10

1 answer

To solve the system of equations using the substitution method, we start with the two given equations:

  1. \( y = -2x + 1 \) (Equation 1)
  2. \( -4x = -2y + 10 \) (Equation 2)

First, we can substitute \( y \) from Equation 1 into Equation 2.

Starting with Equation 2:

\[ -4x = -2y + 10 \]

Now, substitute \( y \) from Equation 1:

\[ -4x = -2(-2x + 1) + 10 \]

Now, simplify the right side:

\[ -4x = 4x - 2 + 10 \] \[ -4x = 4x + 8 \]

Next, let's add \( 4x \) to both sides to combine like terms:

\[ 0 = 8x + 8 \]

Now, we can isolate \( x \):

\[ 8x = -8 \] \[ x = -1 \]

Now that we have \( x \), we can substitute it back into Equation 1 to find \( y \):

\[ y = -2(-1) + 1 \] \[ y = 2 + 1 \] \[ y = 3 \]

Thus, the solution to the system of equations is:

\[ (x, y) = (-1, 3) \]

In conclusion, the solution is \((-1, 3)\).