It opens upward and the vertex is (2,-6) here are some plotted points: (0,6),(1,-3),(2,-6),(3,-3),(4,6). Hope that helps. I hate graphing but if you do it enough times you'll get the hang of it!
First, find the different of the two weights d = 1,200 - 550 d = 650
The different of the weights is 650
Second, to find the percentage, we should compare the difference to the former weight. So we compare 650 to 1,200, then multiply it to 100% percentage = 650/1,200 × 100% percentage = (65,000/1,200) % percentage = 51.17% percentage = 51%