Math help for Algebra

Question

The revenue for local telephone service providers can by modeled by: L(t)=3804.32t + 84252.07.

Where L(t) represents the revenue in millions of dollars t years since 1990. The revenues in millions of dollars for cellular telephone service providers t years since 1990 can be modeled by C(t) = 6428.29t - 11553.

Determine when (what year) the revenue for cellular telephone providers will be greater than that for local telephone providers.

Answer 1

Set C(t) = L(t) to find when cellular revenue equals local revenues

6428.29t - 11,553 = 3804.32t + 84,252.07

(6428.29 - 3804.32)t = 84,252.07 + 11,553.00

2623.97t = 95,805.07

Solve fot t

t = 95,805.07/2623.97 = 36.511 years after 1990, or mid-2026

If t > 36.511 then C(t) > L(t)

Answer 2

You want C(t) ≥ L(t):

C(t) ≥ L(t)

6428.29t - 11553 ≥ 3804.32t + 84252.07

Solve for t.