y= -2x + 3 3x - 2y = 4 3x-2(-2x+3)=4 3x +4x -6 = 4 7x = 10 /:7 x=10/7= 1 3/7 y=-2x+3 y=-2*10/7 + 3 y=-20/7 + 3 y=-2 6/7 + 3 y = 1/7 odp: {x=1 3/7 {y=1/7 2) a) 7x + 2x²-10=0 a=2 b=7 c=-10 Δ=b²-4ac = 49 + 80 = 129 √Δ=√129 x1=(-b-√Δ)/2a = (-7-√129)/4 x2=(-b+√Δ)/2a = (-7+√129)/4 b) 3x²-7x+2=0 Δ=49 -24=25 √Δ=5 x1=(7-5)/6 = 1/3 x2=(7+5)/6 = 2
1. [latex]y=-2x+3\3x-2y=4[/latex] [latex]3x-2(-2x+3)=4\3x+4x-6=4\7x=10\x=frac{10}{7}[/latex] [latex]y=-2cdotfrac{10}{7}+3=-frac{20}{7}+frac{21}{7}=frac{1}{7}[/latex] [latex]x=frac{10}{7}\y=frac{1}{7}[/latex] 2. a) [latex]2x^2+7x-10=0\Delta=49+80=129\x_1=frac{-7-sqrt{129}}{4} vee x_2=frac{-7+sqrt{129}}{4}[/latex] b) [latex]3x^2-7x+2=0\Delta=49-24=25\x_1=frac{7-5}{6}=frac{1}{3} vee x_2=frac{7+5}{6}=2[/latex]
