The radius of a fluorine atom is about 5×10−8 millimeter. The radius of a strontium atom is about 2×10−7 millimeter. About how many times larger is the radius of a strontium atom than the radius of a fluorine atom?

step-by-step explanation:

step 1: solve one of the equations for one of the variables. let's solve the first equation for y:

step 2: substitute that equation into the other equation, and solve for x.

step 3: substitute x = 4 x = 4 x=4 into one of the original equations, and solve for y.