SOLUTION: For the equations a^x /a^y=a^-10 and (a^y)^3=a^-x, if a>1,what is the value of x? 2.5 -7.5 2 1

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: For the equations a^x /a^y=a^-10 and (a^y)^3=a^-x, if a>1,what is the value of x? 2.5 -7.5 2 1      Log On


   

Question 1119245: For the equations a^x /a^y=a^-10 and (a^y)^3=a^-x, if a>1,what is the value of x?
2.5
-7.5
2
1
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
x-y=-10 from the first equation
y=x+10
(a^x+10)^3=a^(-x)
a^3x+30=a^(-x)
-x=3x+30
-4x=30
x=-7.5