Question

For what values of x does the binomial 2x−1 take on a positive value?

For what values of y does the binomial 21−3y take on a negative value?
For what values of c does the binomial 5−3c take on a value which is greater than 80?

Answer 1

1). 2x-1>0
2x>1
x>½

2) 21-3y<0
-3y<-21
y>7

3) 5-3c>80
-3c>75
c<-25