Which expression makes the equation true?

1.) Y^20 = ( )^2
A.) y^4
B.) y^5
C.) y^10
D.) y^12

2.) 100m^20 = ( )^2
A.) 10m^20
B.) 10m^10
C.) 50m^10
D.) 50m^20

Respuesta :

1. C. 

The rule of powers is that when a parenthesis is raised to a power, you multiply the two numbers. Since it is being raised to the second power, it needs to have a 10 in the parenthesis. That would make 20. 

2. B

Firstly 10^2 = 100, so we know that the number must be 10. That leaves us with just A and B. Then we know the same thing from the previous equation, that they need to be multiplied together.