Question

Resuelve las ecuaciones de primer grado.
de la 15 a la 20 por favor.

1be7db84bebd1dfe1ffa29fac4c6b285.pdf

Answer 1

Respuesta:

15.

$3 + 8(6 - x) = - 2(x - 5)$

$3 + 48 - 8x = - 2x + 10$

$- 8x + 2x = 10 - 3 - 48$

$- 6x = - 41$

$- 6x \times ( - \frac{1}{6} ) = - 41 \times ( - \frac{1}{6} )$

$x = \frac{41}{6}$

16.

$\frac{2}{3} x - \frac{1}{5} = 2$

$\frac{2}{3} x = 2 + \frac{1}{5}$

$( \frac{2}{3} )x = \frac{11}{5}$

$( \frac{2}{3} ) \times ( \frac{3}{2} )x = (\frac{11}{5} ) \times ( \frac{3}{2} )$

$x = \frac{33}{10}$

17.

$9x - 15 = - \frac{9}{7}$

$9x = 15 - \frac{9}{7}$

$9x = \frac{96}{7}$

$( \frac{1}{9} ) \times (9x) = ( \frac{96}{7} ) \times ( \frac{1}{9} )$

$x = \frac{32}{21}$

18.

$\frac{3}{10} x - \frac{2}{15} = - \frac{4}{5}$

$\frac{3}{10} x = \frac{2}{15} - \frac{4}{5}$

$\frac{3}{10} x = \frac{ - 10}{15}$

$( \frac{3}{10} ) \times ( \frac{10}{3} )x = - (\frac{10}{15} )\times ( \frac{10}{3} )$

$x = - \frac{20}{9}$

19.

$\frac{x - 2}{5} + \frac{x}{4} = 2$

$\frac{4(x - 2) + 5x}{20} = 2$

$(20) \times ( \frac{4x - 8 + 5x}{20} ) = (2) \times (20)$

$4x + 5x - 8 = 40$

$4x + 5x = 40 + 8$

$9x = 48$

$( \frac{1}{9}) \times (9x) = (48) \times ( \frac{1}{9} )$

$x = \frac{16}{3}$

20.

$\frac{x - 2}{9} + \frac{x - 7}{3} = - 4$

$\frac{(x - 2) + 3(x - 7)}{9} = - 4$

$(9) \times ( \frac{x - 2 + 3x - 21}{9} ) = ( - 4) \times (9)$

$x - 2 + 3x - 21 = - 36$

$3x + x = - 36 + 2 + 21$

$4x = - 13$

$( \frac{1}{4} ) \times (4x) = ( - 13) \times ( \frac{1}{4} )$

$x = - \frac{13}{4}$