Question

homeroom morning work quarter 3
math blitz #4 - writing equations & inequalities
write a linear equation or inequality that models the situation. clearly define your variables.
part a: equations

1. concert tickets

each concert ticket costs $25. the total cost is $25 times the number of tickets, plus a $10 online service fee. write an equation that represents the total cost c for buying t tickets.

1. babysitting job

maria earns $12 per hour babysitting. she already has $40 saved up. write an equation for maria’s total money m after babysitting h hours.

1. cell phone plan

a cell phone company charges $50 per month plus $0.05 per text message. write an equation for the total monthly cost c if you send m text messages.

Explanation:

Step1: Define variables & cost components

Let $C$ = total cost, $t$ = number of tickets. Ticket cost: $25t$, fixed fee: $10$.
$C = 25t + 10$

Step2: Define variables & money components

Let $M$ = total money, $h$ = hours babysat. Earned money: $12h$, saved money: $40$.
$M = 12h + 40$

Step3: Define variables & cost components

Let $C$ = monthly cost, $m$ = text messages. Plan fee: $50$, text cost: $0.05m$.
$C = 0.05m + 50$

Answer:

1. $C = 25t + 10$
2. $M = 12h + 40$
3. $C = 0.05m + 50$