Since you subtract 6 and you have to find the sixth term, you can do:
-6×5=-30 ( negative shows you're subtracting and since 75 is the first term, then you have to find the difference of the input/term 6-1, the sixth term minus the first)
75-30=45
You can check by actually continuing the pattern.
75,69,63,57,51,45,39......
Answer:
Step-by-step explanation:
x² - 12x + a = (x + b)²
x² - 12x + a = x² + 2xb + b²
-12 = 2b and a = b²
b = -6
a = b² = 36
Write it in y= mx+b form. Subtract 5x from both sides to get 4y = -5x + 100. Divide by 4 so the answer would be y= -5/4x + 25.
From the given table, the points can be written as : (6,7.55) , (12,7.85), (18, 8.15) and (24, 8.45)
Slope 
m = 
m = 0.05
slope intercept form of line = 
We plug m = 0.05, x = 6 and y = 7.55 and find c.

c= 7.25
Required equation:
... Answer