Which of the following situations involve opposite quantities combining to make 0 ?

Can someone check if i did this correct. it’s number 4 if you’re wondering.

Graph g(x)=2cosx . use 3.14 for π . use the sine tool to graph the function. graph the function by plotting two points. the first point must be on the midline and closest to the origin. the second point must be a maximum or minimum value on the graph closest to the first point.

When 142 is added to a number the result is 64 more then 3 times the number. option 35 37 39 41