X represents nickels
y represents dimes
x+y=29
5x+10y=210
multiply the first equation by -5 (elimination method)
-5x-5y=-145
then add the two equations together
5y=65
divide 5 from both sides
y=13
13 dimes
Answer:

Step-by-step explanation:
Given
← factor both numerator and denominator
=
← cancel common factor (1 - 2b) on numerator/denominator
=
← cancel 6 and 3 by 3
= 
The answer is c first 2×6= 12 then 12-5=7
then do -7×-2=14 the minus signs cancel
finaly we have two bracket so we multiply both number (7)×(14)=98