so use distributive property
which is
a(b+c)=ab+ac so
1/2(x+20)=1/2x+10
and the other
4(6-x)=24-4x
so now we have
1/2x+10=17/4x+24-4x
convert -4x to -16/4x and add to the 17/4x
1/2x+10=1/4x+24
subtract 24 from boths ides
1/2x-14=1/4x
multily both sides by 4
2x-56=x
subtract x from both sides
x-56=0
add 56 to both sides
x=56