48=6*8
54=9*6
56=7*8
64=8*8
63=9*7
<span>1/2*(4-3 1/2x)-1 1/4x+1/2=0
2-1 3/4x-1 1/4x+1/2=0
-1 3/4x-1 1/4x=-2-1/2
-3x=-2 1/2
x=-2 1/2:(-3)
x=-5/2*(-1/3)
x=5/6
</span>3*(5-x)+13-4*(3x-8)=0
<span>15-3х+13-12х+32=0
-3х-12х=-32-13-15
-15х=-60
х=-60:(-15)
х=4
</span>
14x - 6 = 0
14x = 6
x = 6/14 = 3/7
\18+х\:16=1,5:1, решить пропорцию х=6км/ч