(x-5)1/2+5=2 what is possible solution of this equation

What would be the reasons for lines 3 and 4? a. addition property; subtraction property b. addition property; solve c. substitution property; subtraction property d. substitution property; prove

How many heads would you expect if you flipped a coin twice? first, fill in the table below with the correct probabilities. hint: the sample space for flipping a coin twice is {hh, ht, th, tt}. a = b = c = f