Enter your answer and show all the steps that you use to solve this problem in the space provided. Your local gas stations are having a price war. During the past 7 days they have lowered the price of regular gas by $.02 each day. Define a variable. Then write and solve an equation to find the total change in gas price. Show your work.
step 1
define the variables
x -----> number of days
y ----> the total charge
P ---> intial price before the 7 days
the linear equation in slope intercept form is equal to
y=mx+b
In this problem we have
m=-0.02 ( is teh slope or unit rate)
b=P ( is the y-intercept or initial value)
substitute
y=-0.02x+P
For x=7 days
y=-0.02*(7)+P
y=-0.14+P ----> this is the equation for the price after 7 days
the total change in 7 days is -$0.14