Complete

[@kjustinv]

For question #4: why can't we plug in the 2 to the equation 3a - 2b?

[@houdasrhir3216]

Even if you do, you still don't know anything about b, therefore statement 2 is not sufficient.

[@akankshauniyal1002]

In the 1st question, when we solve for option 2, it gives us the value of xy 48 & -48, isn't it insufficient? As we don't know one value of xy?

[@alessandrofusco4438]

Yes exactly i have the same doubt

[@saroha379]

it A not D

[@lingwang1986]

The answer should be A, not D

[@houdasrhir3216]

@@lingwang1986 Yes the answer is A and not D

[@caroleg1997]

Hy cant the answer be (B) b²- a²/2. Why did you have to negate the b equation and not the a?

[@parthadlakha1641]

I prefer liquid ink to refill my markers. And you should too!