Question 290994
(-2m)^2(4m^7)^2
Squaring an expression is the same as multiplying the expression by itself 2 times. 
(-2m)(-2m)(4m^7)
Multiply -2m by -2m to get 4m^2
(4m^2)(4m^7)^2
Remove the parentheses around the expression 4m^2
4m^2(4m^7)^2
Expand the exponent (2) to the expression.
(4m^2).4^2m^7^2
Multiply 7 by 2 to get 14. 
(4m^2).16m^14
Squaring a number is the same as multiplying the number by itself  In this case, 4 squared is 16.
(4m^2).16m^14
Multiply  by each term inside the parentheses.
64m^16

The answer is 64m^16