Respuesta :

The r would be the number 1 because you would have to make the 2 and 10 equal and 5 x 2 equals 10. 1+1=2.

Does r represent a particular thing? If not then -0.6 because...
10÷2 is 5.
2÷5 is 0.4.
0.4-1 is -0.6.