Answer:
1. -3 × Equation [A1] --> Equation [B1]
2. 7 × Equation [B2] + Equation [B1] --> Equation [C1]
Step-by-step explanation:
There isn't a very elegant way to do this, you just need to brute force it a little and see which options are completely unreasonable and can be skipped. This is what I managed to figure out:
1. -3 × Equation [A1] --> Equation [B1]
6x × -3 = -18x
-7y × -3 = 21y
14 × -3 = -42
2. 7 × Equation [B2] + Equation [B1] --> Equation [C1]
(4x × 7) + -18x = 28x - 18x = 10x
(-3y × 7) + 21y = -21y + 21y = 0y
(-4 × 7) + -42 = -28 - 42 = -70
I can try to explain more about how I got those if you want, but like I said, there isn't much of a method to it other than trial and error.
