## Intermediate Algebra (12th Edition)

According to page 267, $a^{0}=1$ (where $a$ is a nonzero real number). In other words, we know that any nonzero real number raised to a power of 0 will equal 1. Therefore, a. $9^{0}=1$ b. $-9^{0}=-(9^{0})=-(1)=-1$ c. $(-9)^{0}=1$ d. $-(-9)^{0}=-(1)=-1$