You can divide everything by “4” which would end up with the answer being
5-2x over 1 which would be just 5-2x
a)
he charges a fixed cost of $12, meaning a one-time charge of 12 bucks, plus 1.50 for each window.
1 window................ 12 + 1.5(1)
2 windows............. 12 + 1.5(2)
3 windows............. 12 + 1.5(3)
4 windows............. 12 + 1.5(4)
x windows............. 12 + 1.5(x)
b)
Answer:
(x+8)(x+8)
Step-by-step explanation:
<em>Assuming x2 is x^2 </em>
(x+8)(x+8) = x^2 + 16x + 64
Continuation
The Zeros Would Be
x = -8
Answer:
-2.4 + 3.2t
Step-by-step explanation:
-3.6 - 1.9t + 1.2 + 5.1t
-2.4 + 3.2t Add like terms
Answer:
Mean = 78.2
Standard deviation = 5.8
Step-by-step explanation:
Mathematically z-score;
= (x-mean)/SD
From the question;
12% of test scores were above 85
Thus;
P( x > 85) = 12%
P(x > 85) = 0.12
Now let’s get the z-score that has a probability of 0.12
This can be obtained from the standard normal distribution table and it is = 1.175
Thus;
1.175 = (85 - mean)/SD
let’s call the mean a and the SD b
1.175 = (85-a)/b
1.175b = 85 - a
a = 85 - 1.175b ••••••••(i)
Secondly 8% of scores were below 70
Let’s find the z-score corresponding to this proportion;
We use the standard normal distribution table as usual;
P( x < 70) = 0.08
z-score = -1.405
Thus;
-1.405 =( 70-a)/b
-1.405b = 70-a
a = 70 + 1.405b ••••••(ii)
Equate the two a
70 + 1.405b = 85 - 1.175b
85 -70 = 1.405b + 1.175b
15 = 2.58b
b = 15/2.58
b = 5.81
a = 70 + 1.405b
a = 70 + 1.405(5.81)
a = 78.16
So mean = 78.2 and Standard deviation is 5.8
