What is the variable of d/2 + 2 = -3

When turned about its axis of rotation, which shape could have created this three-dimensional object?

Which of the following is true about the graph of f(x)=7^x. select all that apply. a= it intercepts the x axis b=it intercepts both axis c=it intercepts neither d=it intercepts the y axis

X+ y = 5 ; x - y =3 solve using linear combination