Question

ecuaciones de primer grado
1) 2×+5-3×+2=-3×+2-8×+12×​

Answer 1

- Solución:

• Resolvemos la ecuación:

$2x + 5 - 3x + 2 = - 3x + 2 - 8x + 12x \\ - x + 7 = x + 2 \\ - x - x = 2 - 7 \\ - 2x = - 5 \\ x = \frac{ - 5}{ - 2} \\ x = \frac{5}{2}$

• Comprobamos:

$2x + 5 - 3x + 2 = - 3x + 2 - 8x + 12x \\ \frac{2}{1} \times \frac{5}{2} + 5 - \frac{3}{1} \times \frac{5}{2} + 2 = \frac{ - 3}{1} \times \frac{5}{2} + 2 - \frac{8}{1} \times \frac{5}{2} + \frac{12}{1} \times \frac{5}{2} \\ \frac{2 \times 5}{1 \times 2} + 5 - \frac{3 \times 5}{1 \times 2} + 2 = \frac{ - 3 \times 5}{1 \times 2} + 2 - \frac{8 \times 5}{1 \times 2} + \frac{12 \times 5}{1 \times 2} \\ \frac{10}{2} + 5 - \frac{15}{2} + 2 = \frac{ - 15}{2} + 2 - \frac{40}{2} + \frac{60}{2} \\ \frac{10 - 15}{2} + 7 = \frac{ - 15 - 40 + 60}{2} + 2 \\ \frac{ - 5}{2} + 7 = \frac{5}{2} + 2 \\ \frac{ - 5}{2} + \frac{7}{1} = \frac{5}{2} + \frac{2}{1} \\ \frac{2 \div 2 \times - 5 + 2 \div 1 \times 7}{2} = \frac{2 \div 2 \times 5 + 2 \div 1 \times 2}{2} \\ \frac{ - 5 + 14}{2} = \frac{5 + 4}{2} \\ \frac{9}{2} = \frac{9}{2}$