Aline that passes throught the points (2,-3) and (b,7) is parallel to the line y=-2x+17. find the value of b

Given that (x-3) is a factor of f(x)=x^3+ax^2-x-6, find a and hence the number of real roots or the equation f(x)=0

An an average person has 6×10 by the power of two as many red blood cells as white blood cells a small sample of the blood has 7×10 by the power of three white blood cells about how many red blood cells are in the sample

100 points? me its important ‼️‼️‼️‼️‼️‼️‼️‼️‼️‼️‼️