(4х+1)(х-1)=9
4х² --4х+х-1=9
4х<span>² -</span>-3х-10=0
D=9-4*(-10)*4=169
х1=-(-4)+13/2*4=17/8=2,1/8
х2=-(-4)-13/2*4=-9/8=-1,1/8
B-3
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(х^5)^2 * х^4 / х^13=x
(-1*1/3*a*b^4*c^2)^3=-(1/27) a^3 b^12 c^6
-(-3b^3)^2 * 3b^3= -27 b^9
5m-3n=5(-2/5)-3•2/3=-2-2=-4