Select an equivalent form of this equation: x/12 - 7 = x/4

The function ƒ is defined by ƒ(x) = (x + 3)(x + 1). the graph of ƒ in the xy-plane is a parabola. which interval contains the x-coordinate of the vertex of the graph of ƒ?

Look at attachment. has all info needed. need

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?