Multiply the number outside the parentheses by each term inside the parentheses
=2(6.1x+25.3y+2.1x-3.9y)
=(2*6.1x)+(2*25.3y)+(2*2.1x)+(2*-3.9y)
=12.2x + 50.6y + 4.2x - 7.8y
combine like terms
= 16.4x + 42.8y
=4(4.1x+ 10.7)
=(4*4.1x) + (4*10.7y)
=16.4x + 42.8y
ANSWER: Yes, the two expressions are equivalent.
Hope this helps! :)