Carry out the mult.: f(x) = -[x^2 - 21x + 9x - 189]
Combine like terms: f(x) = -[x^2 - 12x - 189]
Eliminate the brackets [ ]: f(x) = -x^2 + 12x + 189
Identify coefficients a, b and c: a= -1, b=12, c=189
The equation of the axis of symmetry is x = -b/(2a), which here equals
x = -(12)/[2(-1)], or x = 6
This is also the x-coordinate of the vertex. Plug x=6 into the original equation to calculate the y-coordinate.
9 a
------ = -----
a 5
a^2 = 45
a = 3<span>√5
</span>
4 b
------ = -----
b 5
b^2 = 20
b = 2√5
answer:
a = 3√5
b = 2√5
hope it helps
down 3 unit mean -3 outside root
right 2 unit mean -2 inside root,
so the answer is
Answer:0.29
Step-by-step explanation:
An average of six cell phone thefts is reported in San Francisco per day. This means our mean value, u = 6
For poisson distribution,
P(x=r) = (e^-u×u^r)/r!
probability that four cell phones will be reported stolen tomorrow=
P(x=4)= (e^-6×6^4)/4!
= (0.00248×1296)/4×3×2×1
= 3.21408/24=
0.13392
P(x=5)= (e^-6×6^5)/5!
= (0.00248×7776)/5×4×3×2×1
= 19.28448/120
= 0.1607
probability that four or five cell phones will be reported stolen tomorrow
= P(x=4) + P(x=5)
= 0.13392 + 0.1607
= 0.294624
Approximately 0.29
