5x+ 10= -4x -17
⇒ 5x+ 4x= -17 -10
⇒ 9x= -27
⇒ x= -27/9
⇒ x= -3
Final answer: x=-3~
T = -20 so
t+1= -20 + 1
= -19
Combinatorial Enumeration. That whole class was a rollercoaster ride of mind-blowing generating functions to prove crazy things. The exam had ridiculous questions like 'count the number of cactus trees with n vertices such that etc etc etc' and you'd do three pages of terrible terrible sums and algebra. Then your final answer would be something beautiful like n/2 and you'd breath a sigh of relief and thank the math gods.
Answer: it will take 125 additional minutes for both costs to be equal.
Step-by-step explanation:
Let a represent the number of additional minutes that it will it take for the two to be the same.
Company A charges a flat fee of 59.99 a month and .43 additional minutes. This means that the total cost of a additional units would be
0.43x + 59.99
Company B charges 69.99 a month and .35 for additional minutes. This means that the total cost of a additional units would be
0.35x + 69.99
For the cost of the two plans to be the same, it means that
0.43x + 59.99 = 0.35x + 69.99
0.43x - 0.35x = 69.99 - 59.99
0.08x = 10
x = 125