Answer :
Step-by-step explanation:
A. For Tavon's gift card the equation is
let y be the total amount
let x be the number of 30 day period
y=145-3.5x------1
for Tavon's second gift card the equation is
let y be the total amount
let x be the number of 30 day period
y=125-3x-------------2
B. equating 1 and 2 we have
145-3.5x=125-3x
solve for x we have
145-125=-3x+3.5x
20=0.5x
divide both sides by x we have
x=20/0.5
x= 40
put x=40 in
y=145-3.5*40------1
y=145-140
y=$5
put x=40 in
y=125-3*40------1
y=125-120
y=$5