Question 29278
Let the nickels be x
Let the dimes be y
x+y=50 solve for y
y=50-x (subsitution)


Nickel value  x 100 = 5 
Dime value x 100 = 10
Total value x 100 = 430


Equation:
5x+10y=430
Subsitute for y
5x+10(50-x)=430
5x-10x=430-500
-5x=-70
x=14


y=50-14
y=36



Hence, there are 14 nickels and 36 dimes.
Paul.