Marta's weekly pay for selling large screen televisions is determined by the formula

Question

S= $275 + 80n
where s is her pay in dollars, and n is the number of large televisions she sells that week.
If Marta's pay last week was $835, how many large screen televisions did she sell?

Answer 1

$275 + 80n = $835

275-275 +80n = 835-275

80n = 560

80n/80 = 560/80

n = 7