6 4/7 × 14/23 - 1 5/6 ÷ 5 1/2 + 13 3/4 = 17 5/12
1) 6 4/7×14/23= 46/7×14/23=4
2) 1 5/6 ÷ 5 1/2= 11/6 ÷ 11/2=11/6 × 2/11=1/3
3) 4-1/3=3 2/3
4) 3 2/3+13 3/4=17 5/12
А) х²+19х+48=0
а=1,b=19,c=48.
D=b²+4ac=19²+4*1*48=361+192=553>0
-b+√D -19+23,5
x¹=----------=-------------=2,25
-b-√D -19-23,5 -42,5
x²=--------=------------=--------=-21,25
Ответ;:-21,25 и 2,25
2a 2 2
2a 2
АВ= Ι2,5-(-3)Ι=5,5
АВ=Ι-2 1/4-(-3/4)Ι= Ι-1 2/4Ι= Ι-1 1/2Ι = 1 1/2
234+26-x=96 x=96-234-26 -x=-164⇒x=164