Answer:
9x^2 -4
Step-by-step explanation:
(3x+2) (3x-2)
FOIL
first: 3x*3x = 9x^2
outer: 3x*-2 = -6x
inner: 3x*2 = 6x
last: -2*2 = -4
Add together
9x^2 -6x+6x -4
9x^2 -4
Answer:
first one
Step-by-step explanation:
Tracey bought 10 movies
some cost 13 and the others 16
Let x be the movies that cost 13 and y ones that cost 16
we can state that
since Tracey both ten
since the total price is 139
so the system is :
Answer:
2/3
Step-by-step explanation:
The slope of a line given two points is
m = (y2-y1)/(x2-x1)
= (4-2)/(0 - -3)
= (4-2)/(0+3)
= 2/3
Angle c (36 degree) is equal to angle a
Angle a=36 degree
a+b=180
b=180-36
b=144 degree
Angle b=144 degree
Answer:
Using z score formula:
X = z ∂ + µ
= 157.833
Step-by-step explanation:
Solution:
Mean = µ = 1262
Standard deviation = ∂ = 117
(a) 28th percentile for the number of chocolate chip.
P( z < z) = 28%
= 0.28
P( z<- 0.58) = 0.28
Z = -0.58
By using z score formula:
Z = x - µ /∂
-0.58= x – 117 / 1262
X = (- 0.58)(117) + (1262)
= 1194.14
(b) Middle 97% of bag.
P(-z < z < z) = 97%
= 0.97
P( z < z) – p(z < -z) = 0.97
2p(z < z) -1 = 0.97
2p (z < z) = 1 + 0.97
P(z < z) = 1.97 / 2
= 0.99
P(z < 2.33) = 0.99
Z ± 2.33
By using z score formula:
Z = x - µ / ∂
X = z ∂ + µ
= - 2.33 x 117 + 1262
=989.39
Z = 2.33
X = z ∂ + µ
= 2.33 x 117 + 1262
=1533.61
(c) What is the interquartile range of the number of chocolate chips in a bag of chocolate.
By using standard normal table,
The z dist’n formula:
P(z < z ) = 25%
=0.25
P(z < -0.6745) = 0.25
Z = 0.6745
Using z score formula:
X = z∂ + µ
= - 0.6745 x 117 + 1262
= 1183.0835
First quartile = Q1 =1183.0835
The third quartile is:
P(z<z) = 75%
= 0.75
P(z < 0.6745) = 0.75
Z = 0.6745
Using z score formula:
X = z ∂ + µ
= 0.6745 x 117 + 1262
= 1340.9165
IQR = Q3 – Q1
= 1340.9165 – 1183.0835
= 157.833
