The slope of a line is 3/2 and the line contains the points (5,9) and (3, a). what is the value of a?

Y = mx + b
slope(m) = 3/2
(5,9)...x = 5 and y = 9
now we sub and find b, the y int
9 = 3/2(5) + b
9 = 15/2 + b
9 - 15/2 = b
18/2 - 15/2 = b
3/2 = b
so ur equation is : y = 3/2x + 3/2(3,a)so x = 3

y = 3/2(3) + 3/2
y = 9/2 + 3/2
y = 12/2
y = 6

so ur missing value is 6...a (or y)  = 6