Answer:
x² - 20 = 0
Using the quadratic formula

a = 1 b = 0 c = -20
So we have

Hope this helps you.
Which page is this in the book
Answer & Step-by-step explanation:
The formula is given in the middle. You are supposed to insert the value of x into this formula to find the value of y (like in the first given example):

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:Done
Find the distance of each trip:
68 km / 34 trips = 2 km per trip
Divide total distance by distance per trip:
348 km / 2 km per trip = 174 trips
Answer: 174 trips