Answer: 
Step-by-step explanation:
Perpendicular lines have slopes that are negative reciprocals, so as the slope of the given line is -5/4, the slope of the perpendicular line is 4/5.
Substituting into point-slope form,
Missing questions and subsequent solutions:
(a) Write an equation for company A for cost, C, number of months, n, that Beni will pay for the phone.
Solution:
For company A:
C = 72.25 + 85.50n
(b) Write an eqyation for company B for cost, C, and number of months, n, that Bei will pay for the phone.
Solution:
For company B:
C = 151.25 + 65.75n
(c) Write an inequality when the cost from company A is better than cost from company B.
Solution:
72.25 + 85.50n ≤ 151.25 + 65.75n
(85.50-65.75)n ≤ (151.25 - 72.25)
19.75 n ≤ 79
n ≤ 4
(d) Value of n for which cost from the two companies will be the same.
Solution:
If cost for companies A and B are the same, then
72.25 + 85.50n = 151.25 + 65.75n
(85.5 - 65.75)n = 151.25 - 72.25
19.75n = 79
n = 79/19.75 = 4 months
After 4 months,
C = 72.25 + 85.5*4 = $414.25
Answer:
Step-by-step explanation:
First you factor 
:
Then you factor out 
from 
:
Then you factor out 7 from 
:
Factor out common term 
:
Factor 
:
Use the perfect square formula:
Cancel out common factor :
