When n = 1 first term = -6
n = 2 second term = 0
n = 3 third term = 6
n = 4 4th term = 12
so we have an Arithmetic sequence first term = -6 and common difference = 6
Sum 14 terms = (14/2)[2*-6 + (14-1)*6]
= 462 answer
Answer:
V1 = 60 km/h
V2 = 40 Km/h
Step-by-step explanation:
The speed of an object is defined as
Speed = distance / time
Let
V1 be the speed of the faster car
V2 be the speed of the other car
t1 the time it took for the first car to arrive
t2 the time it took for the second car to arrive
d1 the distance traveled by first car
d2 the distance traveled by second car
We know thanks to the problem that
V1 = V2 + 20 Km/h
t1 = t2 - 1 hour
d1 = d2 = 120 Km
d1 = V1 * t1
d2 = V2* t2
V1 * t1 = V2* t2
V1* t1 = (V1 -20)*(t1 +1)
The system of equations
(V1 -20)*(t1 +1) = 120
V1 * t1 = 120
120 + (120/t1) -20*t1 = 140
(120/t1) -20*t1 = 20
Which gives,
t1 = 2
This means
V1 = 60 km/h
V2 = V1 - 20 Km/h = 40 Km/h
12, 3/4=12.75. 2, 1/2=2.5. All you have to do is multiple base * height to get your answer. so 12.75*2.=31.875.
Answer: 
<u>Step-by-step explanation:</u>
To find the tangent, you need to find the derivative with respect to x.
Then substitute x = 1 into the derivative.
Given: 0 = 2x² - xy - y²
Derivative: 0 = 4x - y' - 2yy'
Solve for y': 2yy' + y' = 4x
y'(2y + 1) = 4x
