Question

3. How many solutions are there to the following system of equations?

3x + 7y = –10
15x + 35y = –45

(Points : 4)
0
1
2
infinitely many

Answer 1

\[3x + 7y = –10\\
15x + 35y = –45\] multiply the first equation by \(5\) and you get
\[15x + 35y = –50 \\
15x + 35y = –45\]
both the left hand sides are identical, but the right hand sides are different, so you cannot solve it. i.e. the lines are parallel