Answer:
40-10=30
Step-by-step explanation:
x-10=30
we are going to flip the problem which would make it addition so you would do 10+30=X and we can fill in the blank of x equalling 40 because 10+30 is 40
x = 40
x - 10 = 30
=> x = 30 + 10
=> x = 40
