Answer:
-1.2 or -11/9 or -1 2/9
Step-by-step explanation:
Answer: a) Required minimum sample size= 219
b) Required minimum sample size= 271
Step-by-step explanation:
As per given , we have
Margin of error : E= 5% =0.05
Critical z-value for 90% confidence interval : 
a) Prior estimate of true proportion: p=28%=0.28
Formula to find the sample size :-

Required minimum sample size= 219
b) If no estimate of true proportion is given , then we assume p= 0.5
Formula to find the sample size :-

Required minimum sample size= 271
Slope intercepf is y=mx+b wherem=slope and b= y intercept
slope is found by doing
(y1-y2)/(x1-x2)
points are (6,-1) and (-3,2)
(x,y)
x1=6
y1=-1
x2=-3
y2=2
subsitute
(-1-2)/(6-(-2))=-3/(6+2)=-3/8
slope=-3/8
subsitute
y=-3/8x+b
subsitute and solve for b
(-3,2)
x=-3
y=2
2=-3/8(-3)+b
2=9/8+b
2=16/8
subtract 9/8 from both sides
16/8-9/8=b
7/8=b
y=-3/9x+7/8 is the equation
Gio should for sure devide everything by ^2 and then combine like terms.