Question

10−3=36 2+5=−4 _____________ 20X + 50 = -30 + 60 _________________ 5x/7 +2/3 = 4/5

Answer 1

a)

$5x - 30 = 2 \\ \\ 5x = 2 + 30 \\ \\ x = \frac{32}{5} \\ \\ x = 6.4$

b)

$20x + 50 = - 30 + 60 \\ \\ 20x = - 30 + 60 - 50 \\ \\ 20x = - 80 + 60 \\ \\ x = \frac{ - 20}{20} \\ \\ x = - 1$

c)

$\frac{5x}{7} + \frac{2}{3} = \frac{4}{5} \\ \\ \frac{5x}{7} = \frac{4}{5} - \frac{2}{3} \\ \\ \frac{5x}{7} = \frac{(4 \times 3) - (5 \times 2)}{5 \times 3} \\ \\ \frac{5x}{7} = \frac{12 - 10}{15} \\ \\ \frac{5x}{7} = \frac{2}{15} \\ \\ 5x = \frac{2}{15} \times \frac{7}{1} \\ \\ 5x = \frac{14}{15} \\ \\ x = \frac{ \frac{14}{15} }{ \frac{5}{1} } \\ \\ x = \frac{14 \times 1}{15 \times 5} \\ \\ x = \frac{14}{75} \\ \\ x = 0.18$

d)

$5(2 + 2x) + 3x = 0 \\ \\ 5 \times( 2 + 2x) =- 3x \\ \\ 5 \times 2 = +5\times2x=-3x\\ \\ 10+10x=-3x\\ \\ 10=-3x-10x\\\\10=-13x \\\\- \frac{10}{13}=x\\\\0,77=x$

Espero que te ayude me costó mucho ʕ´• ᴥ•̥`ʔ