log7x4−log72x2=3 \log_7x^4-\log_72x^2=3 log7x4−log72x2=3
?=x
logax−logay=logaxy \log_ax-\log_ay=\log_a\frac{x}{y} logax−logay=logayx
log7x4−log72x2= \log_7x^4-\log_72x^2= log7x4−log72x2=
log7x42x2=3 \log_7\frac{x^4}{2x^2}=3 log72x2x4=3
73=x22 7^3=\frac{x^2}{2} 73=2x2
We multiply by: 2 2 2
2⋅73=x2 2\cdot7^3=x^2 2⋅73=x2
Extract the root
x=680=714 x=\sqrt{680}=7\sqrt{14} x=680=714
x=−680=−714 x=-\sqrt{680}=-7\sqrt{14} x=−680=−714
−714 , 714 -7\sqrt{14\text{ }}\text{ , }7\sqrt{14} −714 , 714