This intersection means that u have to find the same number in both sets
the answer is 3 , 7 , 13
i am a mathematics teacher. if anything to ask please pm me
y = -1/2x + 5 should be your equation because it is 5 ft above sea level and its eroding, or going down, 1 ft per 20 years. So every year, the sand dune erodes 1/20 ft more.
Hope this helps!
