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
3x200= 600
1000-600=400
400 divided by 5 = 80
answer is 80 adults
can u mark me brainliest?
Name all the angles that have v as a vertex
Perhaps the most concise way to factor is by "completing the square" which is how the quadratic formula is derived...
x^2+6x+8=0 move constant to other side, subtract 8 from both sides
x^2+6x=-8, halve the linear coefficient, square it, then add that to both sides, in this case (6/2)^2=3^2=9
x^2+6x+9=1 now the left side is a perfect square of the form
(x+3)^2=1 take the square root of both sides
x+3=±√1 subtract 3 from both sides
x=-3±√1
x=-3±1
x=-4 and -2
Since the zeros occur when x=-4 and -2 the factors of the equation are:
(x+2)(x+4)