Overestimate because the answer is 1.61
If this is distributive property, you would change 8(3x-6) to 8(3)x-8(6) and another way to say that is 24x-48 so it would be b and for d there are two negative signs which would equal positive so b and d
Answer: in order to qualify, the time must be at least 15.93 minutes
Step-by-step explanation:
Let x be a random variable representing the average response times of fire departments to fire calls. Since it follows a normal distribution, we will determine the z score by applying the formula,
z = (x - µ)/σ
Where
x = sample mean
µ = population mean
σ = population standard deviation
From the information given,
µ = 12.8 minutes
σ = 3.7 minutes
in order to qualify for the special safety award, the probability value would be to the right of the z score corresponding to 80%
The z score corresponding to 80% on the normal distribution table is 0.845
Therefore,
0.845 = (x - 12.8)/3.7
0.845 × 3.7 = x - 12.8
3.13 = x - 12.8
x = 12.8 + 3.13 = 15.93
The vertex form of the equation is:
y = a ( x - h )² + k
- 81 = a ( 0 - 6 )² + 27
- 81 = 36 a + 27
- 108 = 36 a
a = - 108 : 36
a = - 3
y = - 3 ( x - 6 )² + 27
y = - 3 ( x² - 12 x + 36 ) + 27
y = - 3 x² + 36 x - 108 + 27
y = - 3 x² + 36 x - 81
y = - 3 ( x² - 12 x + 27 )
x² - 12 x + 27 = 0
x² - 9 x - 3 x + 27 = 0
x ( x - 9 ) - 3 ( x - 9 ) = 0
( x - 9 ) ( x - 3 ) = 0
x 1 = 3, x 2 = 9
Answer:
The x-intercepts are ( 3, 0 ) and ( 9, 0 ).
