Question

a)y=×-19
b)y=20×-5
c)y=2×+20

d)y=3×-15
e)y=10-100×
f)y=20×-4

g)y=10×-50
h)y=3×-90
i)y=20×-20
j)y=1-×
​

Answer 1

Explicação passo-a-passo:

$a) \: \: x - 19 = 0 \\ x = 19 \ \ \\ \\ \ b) \: \:20x - 5 = 0 \\ 20x = x = \frac{5}{20} = - 4 \\ \\ c) \: \: 2x + 20 = 0 \\ 2x = - 20 \\ x = \frac{20}{2} = 10$

$d) \: \: 3x - 15 \\ 3x = 15 \\ x = \frac{15}{3} = 5 \\ \\ e) \: \: 10 - 100x \\ - 100x = - 10( \times - 1) \\ 100x = 10 \\ x = 10\\ \\ f) \: \: 20x - 4 \\ 20x = 4 \\ x = \frac{20}{4} = 5$

$g)10×-50 \\ 10x = 50 \\ x = \frac{50}{10} = 5 \\ \\ </p><p>h)3×-90 \\ 3x = 90 \\ x = \frac{90}{3} = 30 \\ \\ </p><p>i)20×-20 \\ 20x = 20 \\ x = \frac{20}{20} = 1 \\ \\ </p><p>j)1-× = - x = -1( \times - 1) \\ x = 1$