Answer:
B. y = –2.9x + 13.5
Step-by-step explanation:
You can try to use the calculator to determine the best line for the values given; you will se that the calculator form, for the linear function is
y = a + <em>b</em>x, where a is the y intercept and <em>b </em>is the slope.
To determine the slope, we apply a formula, to calculate the product of the two xy and, x², plus the sum of each column.
x y xy x²
1 . 11 = 11 → x² = 1² = 1
2 . 8 = 16 → x² = 2² = 4
3 . 4 = 12 → x² = 3² = 9
4 . 1 = 4 → x² = 4² = 16
5 . 0 = 0 → x² = 5² = 25
Total x = 1 + 2 + 3 + 4 + 5 = 15
Total y = 11 + 8 + 4+ 1 + 0 = 24
Sum of xy = 11 + 16 + 12 + 4 + 0 = 43
Sum of x² = 1 + 4 + 9 + 16 + 25 = 55
n = 5
So b = 5 (43) - (15) . (24) / 5 (55) - 15² = -2.9
a = y media - b . x media → a = 24/5 - (-2.9) . 15/5 = 13.5
