\(b,63-\left(5x-2\right):11=20\\ \Rightarrow\left(5x-2\right):11=63-20\\ \Rightarrow\left(5x-2\right):11=43\\ \Rightarrow5x-2=43\times11\\ \Rightarrow5x-2=473\\ \Rightarrow5x=473+2\\ \Rightarrow5x=475\\ \Rightarrow x=475:5\\ \Rightarrow x=95\)
\(c,\left(3x-2^4\right).7^{10}=2.7^{11}\\ \Rightarrow3x-16=2.7^{11}:7^{10}\\ \Rightarrow3x-16=2.7\\ \Rightarrow3x-16=14\\ \Rightarrow3x=14+16\\ \Rightarrow3x=30\\ \Rightarrow x=30:3\\ \Rightarrow x=10\)
Bài 2:
a: =>2x=98
hay x=49
b: =>(5x-2):11=43
=>5x-2=473
hay x=95