Question

Rozwiąż równania:
a) -7(x+2) +4 = -3x
b) -4(1/2x - 2) -4 = 2(-x + 2)
c) 2x(x - 1) +4 = 2(x - 1)^2
d) -(x - 2)^2 + 3(x - 7) = 2 -(x + 1)(x - 1)

Answer 1

A)
-7(x+2) +4 = -3x
-7x-14+4 = -3x
-7x+3x =10
-4x = 10/:(-4)
x= -2,5
b)
-4(1/2x - 2) -4 = 2(-x + 2)
-2x+8-4=-2x+4
-2x+2x=-4+4
0=0
c)
2x(x - 1) +4 = 2(x - 1)^2
2x²-2x+4=2(x²-2x+1)
2x²-2x+4=2x²-4x+2
2x²-2x-2x²+4x=2-4
2x=-2 /:2
x=-1
d)
-(x - 2)^2 + 3(x - 7) = 2 -(x + 1)(x - 1)
-(x²-4x+4)+3x-21=2-x²+1
-x²+4x-4+3x-21=2-x²+1
-x²+x²+7x=3+25
7x=28/:7
x=4