[tex]\displaystyle\bf\\\left \{ {{y = 2 {x}^{2} + 3x - 5 } \atop {y = 2x + 1 }} \right. \\ \\ 2{x}^{2} + 3x - 5 = 2x + 1 \\ 2 {x}^{2} + 3x - 2x - 5 - 1 = 0 \\ 2 {x}^{2} + x - 6 = 0 \\ D = {1}^{2} - 4 \times 2 \times ( - 6) = 1 + 48 = 49 \\ x_{1} = \frac{ - 1 + 7}{2 \times 2} = \frac{6}{4} = 1.5 \\ x_{2} = \frac{ - 1 - 7}{2 \times 2} = - \frac{8}{4} = - 2 \\ \\ y_{1} =2 \times 1.5 + 1 = 3 + 1 = 4 \\ y_{2} = 2 \times ( - 2) + 1 = - 4 + 1 = - 3[/tex]
( 1,5 ; 4 ) и ( - 2 ; - 3 )
1,5 + 4 - 2 - 3 = 5,5 - 5 = 0,5
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[tex]\displaystyle\bf\\\left \{ {{y = 2 {x}^{2} + 3x - 5 } \atop {y = 2x + 1 }} \right. \\ \\ 2{x}^{2} + 3x - 5 = 2x + 1 \\ 2 {x}^{2} + 3x - 2x - 5 - 1 = 0 \\ 2 {x}^{2} + x - 6 = 0 \\ D = {1}^{2} - 4 \times 2 \times ( - 6) = 1 + 48 = 49 \\ x_{1} = \frac{ - 1 + 7}{2 \times 2} = \frac{6}{4} = 1.5 \\ x_{2} = \frac{ - 1 - 7}{2 \times 2} = - \frac{8}{4} = - 2 \\ \\ y_{1} =2 \times 1.5 + 1 = 3 + 1 = 4 \\ y_{2} = 2 \times ( - 2) + 1 = - 4 + 1 = - 3[/tex]
( 1,5 ; 4 ) и ( - 2 ; - 3 )
1,5 + 4 - 2 - 3 = 5,5 - 5 = 0,5