Solve the system of equations. x−3y=18 7x−5y=46

(−3, −5)

(33, 5)

(105, 5)

(3, −5)

1 answer

To solve the system of equations:

  1. \( x - 3y = 18 \) (Equation 1)
  2. \( 7x - 5y = 46 \) (Equation 2)

We can solve this using the substitution or elimination method. Here, I’ll use the substitution method.

From Equation 1, we can express \( x \) in terms of \( y \):

\[ x = 3y + 18 \]

Now, we substitute \( x \) into Equation 2:

\[ 7(3y + 18) - 5y = 46 \]

Expanding this:

\[ 21y + 126 - 5y = 46 \]

Combining like terms:

\[ (21y - 5y) + 126 = 46 \]

\[ 16y + 126 = 46 \]

Now, isolate \( y \):

\[ 16y = 46 - 126 \]

\[ 16y = -80 \]

Dividing by 16:

\[ y = -5 \]

Now that we have \( y \), we can find \( x \) using Equation 1:

\[ x = 3(-5) + 18 \]

\[ x = -15 + 18 \]

\[ x = 3 \]

So the solution to the system of equations is:

\[ (x, y) = (3, -5) \]

Thus, the correct answer is:

(3, −5).