<span>49+14х+х</span>²<span>=0
x</span>²+14x+49=0
D=14²-4*1*49=196-196=0
x=-14/2=-7
<span>36z</span>²<span>-12z+1=0
</span>D=(-12)²-4*36*1=144-144=0
z=12/72=1/6
Ответ:
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Объяснение:
-4x-3y=-49
4x+3y=49
4x=49-3y
x=(49-3y)/4
/x,y/=/(49-3y)/4, y/ , y∈R
1+sin2a=sin^2a+2sinacosa+cos^2a=(sin+cos)^2