<span>8(х-3)-4(5х+2)=5х+19,
8х-8·3-4·5х-4·2=5х+19,
8х-24-20х-8=5х+19,
8х-20х-5х=19+24+8,
-17х=51,
х=51:(-17)
х=-3
</span>
Loga b= log c b/log c a
log5 49/log5 2=2*log5 7 /log5 2=2 log2 7
log2 7=1/log7 2
log2 14= log2 2*7=log2 2 + log2 7
2 log2 7 - log2 7 - 1 - log2 7=-1
равно -1
MP²=MK²+PK²-2MK*PK*cosK=768+768+2*768*1/2=768*3=2304
MP=√2304=48