Well let's pretend that decimal wasn't there, and the question was just asking √81. You should know that the answer to √81 is 9. So now, let's put the decimal back in its place so the question is √.81 again. You just have to do the same thing to the answer by adding a decimal in front of it. Therefore:
√81 = 9
√.81 = .9
Your answer is 0.9 :)
Point slope form:
y - y1 = m(x - x1) where m = slope and coordinate point (x1, y1)
In this case y+2= 3(x-7), slope = 3 and a coordinate point (7, -2)
Answer is D
The slope is 3 and (7, 2) is on the line
(7x10)+(4×1)+(9×1\100)+(2×1\100)=74.11