Question

Rozwiąż równania i zrób sprawdzenia :
a) 4x + 1 = 5x - 30
b) 4 (x+ 12 )- 3 = 9x - 35
c) 7x + 36 = 5x - 8 + 4x
d) -5x - 3 - (-x + 8 ) = x

Answer 1

A) 4x + 1 = 5x - 30
4x-5x=-30-1
-1x=-31
x=31
4*31-5*31=-31
124-155=-31
b) 4 (x+ 12 )- 3 = 9x - 35
4x+48-3=9x-35
4x+45=9x-35
4x-9x=-35-45
-5x=-80
x=16
spr; -5*16=-80 -80=-80
c) 7x + 36 = 5x - 8 + 4x
7x-5x-4x=-8-36
-2x=-44
x=21
spr; -2*21=-44 -44=-44
d) -5x - 3 - (-x + 8 ) = x
-5x-3+x-8=x
-4x-11=x
-5x=11
x=-2.2
spr; -4*-2.2-11=-2.2 8.8+2.2=11 11=11

Answer 2

A) 4x + 1 = 5x - 30
-x+1 = -30
-x = -31 /*(-1)
x = 31
spr. 4*31 +1= 5*31 -30
124 +1 = 155-30
12 5=125
b) 4 (x+ 12 )- 3 = 9x - 35
4x+48-3 = 9x-35
-5x+4 = -35
-5x = -80/ :(-5)
x = 16
spr. 4*16+48-3 = 9*16-35
64+45= 144-35
109=109
c) 7x + 36 = 5x - 8 + 4x
7x+36 = 9x-8
-2x+36 = -8
-2x = -44 / :(-2)
x = 22
spr. 7*22+36 = 9*22-8
154+36 = 198-8
190 = 190
d) -5x - 3 - (-x + 8 ) = x
-5x-3+x-8=x
-4x-11=x
-5x-11=0
-5x=11 / :(-5)
x=-2,2
spr. -4*-2,2-11=-2,2
8,8-11=-2,2
-2,2=-2,2

Answer 3

A)
4x + 1 = 5x - 30
5x - 4x = 1 + 30
x = 31
spr:
L = 4x + 1 = 4 * 31 + 1 = 124 + 1 = 125
P = 5x - 30 = 5 * 31 - 30 = 155 - 30 = 125
L = P

b)
4 (x + 12) - 3 = 9x - 35
4x + 4 * 12 - 3 = 9x - 35
4x + 48 - 3 = 9x - 35
4x + 45 = 9x - 35
9x - 4x = 45 + 35
5x = 80
x = 80 : 5
x = 16
spr:
L = 4 (x + 12) - 3 = 4 * (16 + 12) - 3 = 4 * 28 - 3 = 112 - 3 = 109
P = 9x - 35 = 9 * 16 - 35 = 144 - 35 = 109
L = P

c)
7x + 36 = 5x - 8 + 4x
7x + 36 = 9x - 8
9x - 7x = 36 + 8
2x = 44
x = 44 : 2
x = 22
spr:
L = 7x + 36 = 7 * 22 + 36 = 154 + 36 = 190
P = 5x - 8 + 4x = 5 * 22 - 8 + 4 * 22 = 110 - 8 + 88 = 102 + 88 = 190
L = P

d)
-5x - 3 - (-x + 8) = x
-5x - 3 + x - 8 = x
-4x - 11 = x
-11 = x + 4x
-11 = 5x
x = -11 : 5
x = -2,2
spr:
L = -5x - 3 - (-x + 8) = -5 * -2,2 - 3 - (2,2 + 8) = 8 - 10,2 = -2,2
P = x = -2,2
L = P