She is incorrect, she should’ve added 2 to both sides.
The least-square regression line has a slope of:
m=(nΣxy-ΣyΣx)/(nΣx²-ΣxΣx)
and a y-intercept of:
b=(Σy-mΣx)/n
In this case: n=7, Σxy=4899, Σy=391, Σx=85, Σx²=1153 so
m=(7(4899)-391*85)/(7(1153)-85*85))=1058/846
b=(391*846-85*1058)/(7*846)=34408/846
So the line of best fit is:
y=(1058x+34408)/846 and if we approximated this as your answers see to have done....
y=1.25x+40.67
Answer:
The possible length is greater than 29 meters.
Step-by-step explanation:
If the length is x then the width is x - 2 m.
So the perimeter is 2x + 2(x - 2) = 4x - 4 m.
4x - 4 > 112
4x > 116
x > 29 m.