Question

Rozwiąż równania. a)(36-8)x-2x(5-3x)=2(x-4) b)2x-3/6-(3x-7)/8=5x(-3-2x)/3 c)7(x-3)-(2-5)/4=(3x-4)5/3

Answer 1

a)(36-8)x-2x(5-3x)=2(x-4)

36x-8x-10x+6x^2=2x-8

6x^2+36x-8x-10x-2x+8=0

6x^2+16x+8=0

delta=16^2-4*6*8=256-192=64

 

pierw. z del. = 8

x1=-16-8/2*6=-24/12=-2

x2= -16+8/12=-8/12=-2/3

 

 

b)2x-3/6-(3x-7)/8=5x(-3-2x)/3

2x-3/6-3/8x-7/8=-5x-10/3x^2

 

 

c)7(x-3)-(2-5)/4=(3x-4)5/3 

 

7x-21-1/2+5/4=5x-20/3

7x-5x-21-1/2+5/4+20/3=0

 

2x-21-6/12+15/12+80/12=0 

 

2x-21- 89/12=0

2x=341/12

 

2x= 28 i 5/12  /:2

x=14 i5/ 12