Question

Determine o valor de x :
Obrigada dês de ja❕

Answer 1

18)

a) 2x-5=x+1

$2x - 5 = x + 1 \\ 2x - x = 1 + 5 \\ x = 6$

b) 2x+3=x+4

$2x + 3 = x + 4 \\ 2x - x = 4 - 3 \\ x = 1$


c) 5x+7=4x+10

$5x + 7 = 4x + 10 \\ 5x - 4x = 10 - 7 \\ x = 3$

d) 4x-10=2x+2

$4x - 10 = 2x + 2 \\ 4x - 2x = 2 + 10 \\ 2x = 12 \\ \frac{2x}{2} = \frac{12}{2} \\ \\ x = 6$

e) 4x-7=8x-2

$4x - 7 = 8x - 2 \\ 8x - 4x = - 7 + 2 \\ 4x = - 5 \\ x = - 5 \div 4 \\ x = - 1.25$

f) 2x+1=4x-7

$2x + 1 = 4x - 7 \\ 2x - 4x = - 7 - 1 \\ - 2x = - 8 \\ x = ( - 8) \div ( - 2) \\ x = 4$

g) 9x+9+3x=15

$9x + 9 + 3x = 15 \\ 12x = 15 - 9 \\ 12x = 6 \\ x = 6 \div 12 \\ x = \frac{1}{2}$

h) 16x-1=12x+3

$16x - 1 = 12x + 3 \\ 16x - 12x = 3 + 1 \\ 4x = 4 \\ x = 4 \div 4 \\ x = 1$

i) 3x-2=4x+9

$3x - 2 = 4x + 9 \\ 3x - 4x = 9 + 2 \\ - x = 11 \\ x = - 11$

j)5x-3+x=2x+9

$5x - 3 + x = 2x + 9 \\ 5x + x - 2x = 9 + 3 \\ 4x = 12 \\ x = 12 \div 4 \\ x = 3$