Odpowiedź:
a)
4x +15 = -5
4x = -5 - 15 /:4
x = -20/4 = -5
b)
2x + 7 = 4x - 3
2x - 4x = -3 - 7
-2x = -10 /:(-2)
x = 5
c)
-2(x + 3) + 4(2x + 3) = -6
-2x - 6 + 8x + 12 = -6
6x = -6 - 6 /:6
x = -12/6 = -2
d)
x - (7 + 2x) = 2(x - 1) + 1
x - 7 - 2x = 2x - 2 + 1
-x - 2x = -1 + 7
-3x = 6 /:(-3)
x = -2
e)
x/2 - 3/4 = 7/8 + x/4
1/2x - 1/4x = 7/8 + 3/4
2/4x - 1/4x = 7/8 + 6/8
1/4x = 13/8 /*4
x = 13/8 * 4 = 13/2 = 6 1/2
f)
(x + 5)/3 - 5 = x - 2
1/3x + 5/3 - 5 = x - 2
1/3x - x = -2 - 1 2/3
-2/3x = -3 2/3 /*(-3/2)
x = 11/3 * 3/2 = 11/2 = 5 1/2
g)
(x + 4)/5 + (2x + 9)/10 = (-2 - x)/2
1/5x + 4/5 + 1/5x + 9/10 = -1 - 1/2x
2/5x + 1/2x = -1 - 4/5 - 9/10
4/10x + 5/10x = -1 - 8/10 - 9/10
9/10x = -1 17/10 /*10/9
x = -27/10 * 10/9 = 3
Szczegółowe wyjaśnienie:
