Chapter 7 - Exponents and Exponential Functions - 7-6 Exponential Functions - Practice and Problem-Solving Exercises - Page 452: 51

a) $a = 4$ b) $b = 3$ c) $y= 4*3^x$ d) $x= -2, y = 4/9$; $x=4, y=324$

a) $y=a*b^x$ $4 = a*b^0$ $4 = a *1$ $4 = a$ b) $y=a*b^x$ $36 = 4*b^2$ $36/4 = 4*b^2/4$ $9 = b^2$ $3^2 = b^2$ $3 = b$ c) $y=a*b^x$ $y= 4*3^x$ d) $y= 4*3^x$ $y= 4*3^-2$ $y = 4*1/(3^2)$ $y= 4*1/9$ $y=4/9$ $y = 4*3^x$ $y=4*3^4$ $y= 4 * 81 = 324$