Total amount of gas purchased by Ivy's father in the first week = 22.5 gallons
total amount of gas purchased by Ivy's father in the second week = 19.71 gallons
Let us assume the amount of gas purchased by Ivy's father in the third week = x
The total quantity of gas purchased in 3 weeks by Ivy's father = 61.75 gallons
Then
22.5 + 19.71 + x = 61.75
42.21 + x = 61.75
x = 61.75 - 42.21
= 19.54 gallons
So 19.54 gallons of gas was bought by Ivy's father in the third week
C. 30 degrees because it mirrors the angle of P.
First you differentiate to find the gradient
dy/dx = (6 - - 8) / (-4 - 7)
= 14 / -11
= - 14/11
Then you use this formula
y - y1 = m (x - x1)
y1 being the y coordinate
x1 being the x coordinate
m being the gradient (or slope)
y - 6 = -14/11 (x - - 4)
y - 6 = -14/11x - 56/11
y = -14/11x + 10/11