1.46: Logarithmic equations

(a) Solve $\log_a1024=5$. (1)

(b) Solve $\log_3(6c+9)=4$. (2)

(c) Solve $2(\log_b25+\log_b125)=5$. (4)

(d) Solve the equations, giving the values of $x$ and $y$ to 3 significant figures,