Answer:
The third book cost $9.03
Step-by-step explanation:
1. n^2 -8n +16 = 25
Subtract 25 from both sides
n^2 - 8n + 16 - 25 = 0
Simplify
n^2 - 8n - 9 =0
Factor
(n-9)(n+1) = 0
Solve for n
n-9 = 0, n = 9
n+1 = 0, n = -1
Solution: 9,-1
2. C = b^2/25
Multiply both sides by 25:
25c = b^2
Take square root of both sides
b = +/-√25c
Simplify:
b = 5√C, -5√C
3. d = 16t^2 +12t
subtract d from both side:
16t^2 + 12t -d =0
Use quadratic formula to solve:
t = (3 +/-√(9-4d))/8
4. 5w^2 +10w =40
Subtract 40 from both side:
5w^2 + 10w -40 = 0
Factor:
5(w-2)(w+4)=0
Divide both sides by 5:
(w-2)(w+4)=0
Solve for w:
w-2 = 0, w = 2
w+4=0, w = -4
Solution: 2,-4
Answer:
cos 42 = 10 / AB
Step-by-step explanation:
Since this is a right angle, we can use trig functions
cos theta = adjacent / hypotenuse
cos 42 = 10 / AB
Answer:
240000
You have you multiply 40*6,000=240000. So that is your answer.
