Answer:
Option d.
Step-by-step explanation:
The equation of the line of least squares is given as
where 
is the yield of wheat (bushels per acre) and x is the rainfall (in inches).
We need to find the expected number of inches of rain if the yield is 60 bushels of wheat per acre.
Substitute 
in the given equation.
Add 9.12 on both sides.
Divide both sides by 4.38.
The expected number of inches of rain is 15.78.
Therefore, the correct option is d.
Answer:
(0, 4 ) and (2, - 4 )
Step-by-step explanation:
(2)
3x + 4y = 16 → (1)
- 3x + 2y = 8 → (2)
Adding (1) and (2) term by term will eliminate the x- term
0 + 6y = 24
6y = 24 ( divide both sides by 6 )
y = 4
Substitute y = 4 into either of the 2 equations and solve for x
Substituting into (1)
3x + 4(4) = 16
3x + 16 = 16 ( subtract 16 from both sides )
3x = 0 , then
x = 0
solution is (0, 4 )
(3)
2x - 4y = 20 → (1)
5x + 4y = - 6 → (2)
Adding (1) and (2) term by term will eliminate the y- term
7x + 0 = 14
7x = 14 ( divide both sides by 7 )
x = 2
Substitute x = 2 into either of the 2 equations and solve for y
Substituting into (2)
5(2) + 4y = - 6
10 + 4y = - 6 ( subtract 10 from both sides )
4y = - 16 ( divide both sides by 4 )
y = - 4
solution is (2, - 4 )
8.76 + (–3.05)
= 8.76 – 3.05
= 5.71
The answer is c.
