1/4(20-4a)=6-a
We simplify the equation to the form, which is simple to understand
1/4(20-4a)=6-a
Simplifying:
+ 0.25*(20-4a)=6-a
Reorder the terms in parentheses
+(+5-1a)=6-a
Remove unnecessary parentheses
+5-1a=+6-a
We move all terms containing a to the left and all other terms to the right.
-1a+1a=+6-5
We simplify left and right side of the equation.
a=+1
0=1
The left and right sides are not equal, therefore there is no solution. This equation is invalid.