a is the answer, as i is irrational no
Answer:
y = -2x^2 - 4x - 1
Step-by-step explanation:
We can see that the graph passes through (-2, -1), (-1, 1) and (0, -1).
Let's solve
ax^2 + bx + c = y
a(-2)^2 + b(-2) + c = -1
4a - 2b + c = -1
a(-1)^2 + b(-1) + c = 1
a - b + c = 1
a0^2 + b0 + c = -1
c = -1
we got c = -1 so we input it into the other 2
4a - 2b - 1 = -1
4a - 2b = 0
2a - b = 0
2a = b
a - b - 1 = 1
a - b = 2
a = b + 2
Let's input b = 2a
a = 2a + 2
-a = 2
a = -2
b = 2a = 2*(-2) = -4
c = -1
y = -2x^2 - 4x - 1
No, 5/8 is not bigger than 9/10
Answer:
Time taken by the un powered raft to cover this distance is T = 192.12 hr
Step-by-step explanation:
Let speed of boat = u
Speed of current = v
Let distance between A & B = 100 km
Time taken in downstream = 32 hours
u + v = 3.125 ------ (1)
Time taken in upstream = 48 hours
u - v = 2.084 ------- (2)
By solving equation (1) & (2)
u = 2.6045
v = 0.5205
Now the time taken by the un powered raft to cover this distance
Because un powered raft travel with the speed of the current.
T = 192.12 hr
Therefore the time taken by the un powered raft to cover this distance is
T = 192.12 hr
