Tim poured 0.5 liters of water into a beaker and then added 300 milliliters more.what was the total amount of water in the beaker?

The  total  amount  of water  in  the beaker is 0.8  Liters

     calculation

convert   300 Ml in liters
that is  1 L =  1000 Ml
                ?   =  300 Ml
by cross  multiplication

1 L  x300 Ml/   1000  Ml  =  0.3 Ml

total  is therefore =    0.5 Ml +  0.3 Ml  =  0.8   Liters

The lines that match the equations are:
light blue & dark blue

The approximate solution is:
(-1.2, 1.5)