Question

Answer 1

a: 3x+27=9

=>\(3x=9-27=-18\)

=>\(x=-\dfrac{18}{3}=-6\)

b: \(2x+12=3\left(x-7\right)\)

=>3x-21=2x+12

=>3x-2x=21+12

=>x=33

c: \(2x^2-1=49\)

=>\(2x^2=1+49=50\)

=>\(x^2=25\)

=>\(\left[{}\begin{matrix}x=5\\x=-5\end{matrix}\right.\)

d: \(416+\left(x-45\right)=387\)

=>\(x-45=387-416=-29\)

=>x=-29+45=16

e: \(11-\left(x+84\right)=91\)

=>x+84=11-91=-80

=>x=-80-84=-164

f: \(-\left(x+94\right)+213=-16\)

=>\(-\left(x+94\right)=-16-213=-229\)

=>x+94=229

=>x=229-94=135