1/6 = 0.16 with a line over the 6 because it is repeating
M = -1/2
(x₁, y₁) = (-2,-4)
Find the equation
y - y₁ = m(x - x₁)
y - (-4) = -1/2 (x - (-2))
y + 4 = -1/2 (x + 2)
2(y + 4) = -1 (x + 2)
2y + 8 = -x - 2
x + 2y = -10
You are looking for the average. To find the average, one adds all terms and divides by the number of terms.
((1/2)+(5/6))/2
((3/6)+(5/6))/2
(8/6)/2
(4/6)
(2/3)
The answer is B) 2/3.
After understanding the problem, formulate equations to determine the unknown. Let x be the price of one book. Equating Alana&Petra's expense with Angus' would be
5x + 4x +5 = 19x - 10
The 5 in the left side is needed because Angus' expense is $5 more. Also, the 10 on the right side represents the $10 discount. Solving the equation,
19x = 9x = 5+10
10x = 15
x = $1.5
Therefore, the book costs $1.5.