What's the opposite reciprocal of -1/2

algebra i

Paint color preference children adults total 0.6 0.77 liked new paint color disliked new paint color 0.4 0.15 0.23 total 1.0 1.0 1.0 which value for x completes the conditional relative frequency table by column?

The graph shown is the graph of which function?

Solve the following simultaneous equation by using an algebraic method (either substitution or elimination) 2x + 3y=-4 4x-y=11