a)
[tex]\left \{ {{1=-2a+b/*3} \atop {-4=3a+b/*2}} \right. \\+\left \{ {{3=-6a+3b} \atop {-8=6a+2b}} \right. \\3-8=3b+2b\\-5=5b /:5\\-1=b\\1=-2a-1 /+1\\2=-2a /:(-2)\\-1=a\\y=-x-1[/tex]
[tex]b) \\\left \{ {{2=8a+b} \atop {-10=4a+b /*(-2)}} \right. \\+\left \{ {{2=8a+b} \atop {20=-8a-2b}} \right. \\2+20=b-2b\\22=-b\\-22=b\\2=8a-22 /+22\\24=8a/:8\\3=a\\y=3x-22[/tex]
[tex]c)\\+\left \{ {{-\sqrt5=\sqrt2a+b} \atop {3\sqrt5=-\sqrt2a+b}} \right. \\-\sqrt5+3\sqrt5=b+b\\2\sqrt5=2b /:2\\\sqrt5=b\\-\sqrt5=\sqrt2a+\sqrt5 /-\sqrt5\\-2\sqrt5=\sqrt2a /:\sqrt2\\a=-\frac{2\sqrt5}{\sqrt2}=-\frac{2\sqrt{10}}2=-\sqrt{10}\\y=-\sqrt{10}x+\sqrt5[/tex]
