This is the slope formula.
Solving radical equations are different because you would want to get everything in the equation to rational numbers.
Extraneous solutions arise when you manipulate the equation. After manipulating if a solution is found that can not satisfy the original equation(s).
Answer:
I can't see the picture right, it's backward sorry
Step-by-step explanation:
edit the picture and take a better one
1+2+3= 6 (even)
2+3+4= 9 (odd)
it can be both