Answer:
7xy^2 - 2xy^2
Step-by-step explanation:
Subtracting 3xy² from 8xy² is 8xy² - 3xy² = 5xy²
And 7xy^2 - 2xy^2= 5xy²
So y=mx+b
b is the y-intercept or where they cross the y-axis so just set a y-intercept and change the slope
so if y-intercept is 7
y=3x+7
y=2x+7
y=8x+7
y=-1/4x+7
and so on
The answer would be 1 1/3 plotted over the 1 to 1 1/3
The answer is 2x
3
+5x
2
−x−6
Part a is correct.
Part b can be done a couple ways.
1) Use binomial distribution. p = 0.2, n = 144
P(x>3) = 1 - P(x=0) -p(x=1) -p(x=2) -p(x=3)
where

2) Assume a normal distribution with mean = 28.2, stdev = 4.8

Look up z-value in normal table to find probability.
Hope that helps.