If you follow PEMDAS your answer would be 3.6.
The math I used is probably not the quickest way, but for me, the easiest.
25*5=125 25+20=45 45*7=315 125+315=440 25*4=100 440+100=540 5+7+4=16
B is your answer.
Moving from a to b, the x component of the desired vector is 7-(-9) = 16, and
the y component is 3-9 = -6.
So the vector from a to b is <16,-6>, and the magnitude is
sqrt(16^2 + (-6)^2 ), applying the Pythagorean Theorem.
Step-by-step explanation:
7 1/2 = 7 + 1/2 = 14/2 + 1/2 = 15/2 = 7.5
check the attached picture.
:)