y=abx formula help
Can someone help me with the steps to solve this problem?
Darius bought a flat-screen TV for $2200. The value decreases by about 18% each year. How long will it take for the value to be reduced to $500.
My Algebra 2 teacher taught us the formula y = abx where x is an exponent, so I already set up the equation.
500 = 2200(.18) power of x
i got .863 as x but I don't know how long that is in time or if I even did it right.
1. You have to calculate the remaining value. That means: If the value decreases by 18% per year, the remaining value is 88% per year.
Originally Posted by azncocoluver
2. Therefore solve for x:
3. For confrimation: I've got 11.6 years.
I was taught to use a graphing calculator. First you have to move the decimal point two places to the left to get .18. Then you do 1-.18 to get .82. Next you do: . You plug the 500 into [tex]Y1[tex] on a graphing calculator and plug the rest into [tex]Y2[tex]. then you see when the [tex]Y1[tex] and [tex]Y2[tex] are equal.
You did it wrong because it is not .88 it is .82.
Originally Posted by earboth
X is an exponent not a .88X.