To determine whether the system of equations
- \( y = 5x + 7 \)
- \( 3y - 15x = 18 \)
has one solution, no solution, or infinitely many solutions, we can simplify the second equation and see if it is consistent with the first.
First, substitute \( y \) from the first equation into the second equation:
-
Substitute \( y \) in the second equation:
\[ 3(5x + 7) - 15x = 18 \]
Expanding this gives:
\[ 15x + 21 - 15x = 18 \]
The \( 15x \) terms cancel out:
\[ 21 = 18 \]
This is a false statement (21 does not equal 18), which indicates that the two equations are inconsistent.
Thus, the system of equations has no solution.