Решите логарифмические уравнения:

1) Log2 (9-x)=2*log2 (3)

2) log7(x+5)=log7(4x-7)

1)

2)

0} \atop {4x-7>0}} \right.\; \left \{ {{x>-5} \atop {x>1,75}} \right.\; \; \to \; x>1,75\\\\x+5=4x-7\\\\3x=12\\\\\boxed {x=4}" class="latex-formula" id="TexFormula13" src="https://tex.z-dn.net/?f=2%29%5C%3B%20%5C%3B%20log_7%28x%2B5%29%3Dlog_7%284x-7%29%5C%3B%20%5C%3B%20%2C%5Cquad%20ODZ%3A%5C%3B%20%5Cleft%20%5C%7B%20%7B%7Bx%2B5%3E0%7D%20%5Catop%20%7B4x-7%3E0%7D%7D%20%5Cright.%5C%3B%20%5Cleft%20%5C%7B%20%7B%7Bx%3E-5%7D%20%5Catop%20%7Bx%3E1%2C75%7D%7D%20%5Cright.%5C%3B%20%5C%3B%20%5Cto%20%5C%3B%20x%3E1%2C75%5C%5C%5C%5Cx%2B5%3D4x-7%5C%5C%5C%5C3x%3D12%5C%5C%5C%5C%5Cboxed%20%7Bx%3D4%7D" title="2)\; \; log_7(x+5)=log_7(4x-7)\; \; ,\quad ODZ:\; \left \{ {{x+5>0} \atop {4x-7>0}} \right.\; \left \{ {{x>-5} \atop {x>1,75}} \right.\; \; \to \; x>1,75\\\\x+5=4x-7\\\\3x=12\\\\\boxed {x=4}">

y=4(-2,5)-30

y=-10-30

y=-40

-8=4x-30

-4x=-30+8

-4x=-22

x=11/2