First, we look at the left side of the equation.
#-5(2c-12)+2#
We will look at #-5(2c-12)# for now and leave out #+2#.
We will distribute parentheses/brackets using: #x(y+z)=xy+xz#
Therefore, #-5(2c-12)# is the same as #-5*2c cancel(+)-5(-12)#
#-5*2c-5(-12)# is the same as #-5*2c+5*12#.
#5*2c=10c# and #5*12=60#.
Therefore, the equation (with the #+2#) would be #-10c+60+2#.
#60+2=62#
#->-10c+62#
Now we put in the right side of the equation together with the left side.
#-10c+62=20-7c#
We subtract #62# from both sides:
#-10c+62color(blue)-color(blue)62=20-7c color(blue)-color(blue)62#
which is #-10c=-7c-42#
Add #7c# to both sides:
#-10c color(blue)+color(blue)7color(blue)c=-7c-42color(blue)+color(blue)7color(blue)c#
Simplify: #-3c=-42#.
Divide both sides by #3#
#(-3c)/(-3)=(-42)/(-3)#
Simplify:
#c=14#