Answer:
y=x\\
x=y^{2} + 12y\\
y^{2} + 12y -x = 0\\
Delta = (12^{2}) - 4.1.(-x) = 144 +4X = 36.(4+x)
\sqrt{Delta} = 6 . \sqrt{(4+x)} \\
y' = \frac{-12 + 6.(\sqrt{(4+x)}}{2} = -6 + 3.\sqrt{(4+x)}\\
y" = -6 - 3.\sqrt{(4+x)}\\\\
y' = 3.\sqrt{(4+x)} - 6\\
y''= -3.\sqrt{(4+x)} - 6\\
Answer:
1/2
Step-by-step explanation:
When you have two points you need to use the slope formula:

x1 and y1 is the first point and x2 and y2 is the second point, remember that the first number is X and the other is Y so...

1/2 is the slope of the points
Ok so first you take $64.80 and multiply it by 2.5. You get $162. Now take $162 and subtract $20 from it. You are left with $142.
Answer: Cruz's biking is 16 miles per hour and his running speed is 10 miles per hour.
Step-by-step explanation:
Let x represent Cruz's speed when running.
He left his house at 6:00 and ran until 7:30. This means that the time spent while running is 1hour 30 minutes = 1.5 hours.
Distance = speed × time
Distance covered while running would be
1.5 × x = 1.5x
Then he rode his bike until 9:45. This means that the time he spent riding his bike is 2hours 15 minutes = 2 hours + 15/60 = 2.25 hours
His speed when biking was 1.6 times his speed when running. It means his speed when biking would be
1.6 × x = 1.6x
Distance covered while riding would be
1.6x × 2.25 = 3.6x
He covered a total distance of 51 miles. Therefore,
1.5x + 3.6x = 51
5.1x = 51
x = 51/5.1 = 10 miles per hour.
His biking speed would be
1.6 × 10 = 16 miles per hour.