x² +y = 0
x³ -12x -y = 0
<h3>Find</h3>the intersection point(s) (x, y)
<h3>Solution</h3>Add the two equations together, then factor.
... (x² +y) + (x³ -12x -y) = 0 + 0
... x³ +x² -12x = 0
... x(x +4)(x -3) = 0
Then x = {0, -4, 3}.
The corresponding y-values are
... y = -x² = {0, -16, -9}
The points of intersection are (-4, -16), (0, 0), (3, -9)
Answer:
Rate in still water = 27.5 mph
Current's rate = 12.5 mph
Step-by-step explanation:
Let
x mph = row team rate in still water
y mph = current's rate
<u>Upstream:</u>
Distance = 30 miles
Time = 2 hours
Rate = x - y mph
Then
<u>Downstream:</u>
Distance = 30 miles
Time = 45 minutes hour
Rate = x + y mph
Then
From the first equation:
From the second equation:
Add these two equations:
Subtract these two equations: