A number d minus 2 is less then -1

Question

Shouldnt answer be d-2<-1

Answer 1

Your answer is incomplete. You still don't know what d is.

d-2 < -1

add 2 to both sides

d < 1

Check, when d = 1, then 1-2 = -1

but when d, say, = 0.99 (this is less than 1), then 0.99 - 2 = -1.01 < -1, confirming the solution.