Answer:
1. Yes
2. Yes
Step-by-step explanation:
1. Lets test Lisa's different solution. Lets times 5 to the first equation:
and 2 times the second equation:
lets add the two equations:
The second method is multiplying the first equation by -2:
and add the second equation:
The answer to Lisa's question is yes she wull get the same solution if she uses a different method.
2. Yes, The answer would change if the same amout of x and y values are the same and therefore we cannot solve for x and y. If there was infinitely many solutions we would have quadratic equations.