−4x−y=6

8x−9y=10

1 answer

To solve the system of equations given by:

  1. \(-4x - y = 6\)
  2. \(8x - 9y = 10\)

we can use either the substitution method or the elimination method. Here, I'll use the substitution method.

Step 1: Solve for \(y\) in the first equation

From the first equation:

\[ -4x - y = 6 \]

Add \(4x\) to both sides:

\[ -y = 4x + 6 \]

Now, multiply by -1 to solve for \(y\):

\[ y = -4x - 6 \]

Step 2: Substitute \(y\) in the second equation

Now, substitute \(y\) in the second equation:

\[ 8x - 9y = 10 \]

Substituting \(y = -4x - 6\):

\[ 8x - 9(-4x - 6) = 10 \]

Simplify:

\[ 8x + 36x + 54 = 10 \]

Combine like terms:

\[ 44x + 54 = 10 \]

Step 3: Solve for \(x\)

Subtract 54 from both sides:

\[ 44x = 10 - 54 \] \[ 44x = -44 \]

Now, divide by 44:

\[ x = -1 \]

Step 4: Substitute back to find \(y\)

Now substitute \(x = -1\) back into the equation for \(y\):

\[ y = -4(-1) - 6 \] \[ y = 4 - 6 \] \[ y = -2 \]

Conclusion

The solution to the system of equations is:

\[ x = -1, \quad y = -2 \]

In coordinate form, the solution is:

\((-1, -2)\)