Question

СРОЧНО! помогите пожалуйста

Answer 1

${9}^{x} - 4 \times {3}^{x} = 45 \\ {3}^{x} = t \\ {t}^{2} - 4t - 45 = 0 \\ D=(-4)^2-4\times(-45)=16+180=196=14^2 \\ \\ t_{1,2} =\dfrac{4\pm14} {2} =\bigg[^9_{-5} \\ \\ t = {3}^{x} \\ {3}^{x} = 9 \\ x = 2 \\ \\ \\ {3}^{x} = - 5 \\ PeLLIeHuu\:\:HeT$