I attempted an EV calc for fun to play around with different bet sizes etc but i think i did something wrong. It's about this hand by the way. We bet the flop with JJ with 2 outs.

He calls a $1 bet on the flop 100% of the time and we miss 45/47 of the time and lose $1

EV = (45/47)(-1)

He calls the flop 100% and we hit on the turn 2/47 of the time and he calls a $2.50 bet on the turn 100% of the time and calls a $5 river bet 9/10 of the time we win $10.40

EV = (2/47)(9/10)(10.4)

He calls the flop we hit, he calls turn, and raises river (1/10) times, we lose $5.

EV = (2/47)(1/10)(-5)



0 = (45/47)(-1) + (2/47)(1/10)(-5) + (2/47)(9/10)(10.4)

So when i put the above into the algebra solver in spoons mathematics of EV thread it comes out at, '0.580425531914894=0'

But when i put EV in front of the equals sign instead of 0 it comes out at,

EV=-0.580425531914894.

Have i done something wrong? What's the aim of putting a 0 in front of the equals sign instead of EV? I'm confused.