Question

Zad1 .

rozwiąż równanie ;

a) 2(5a-3)-a-4(3a-2)=0

b)2b-(1-b)=11-b

c)2/5(x-2)=x+4

d)3y-2(y-1)=-6

e)3(3-5y)=90-5(3y-2)

Answer 1

A) 2(5a-3)-a-4(3a-2)=0
10a-6-a-12a+8=0
10a-a-12a=-8+6
-3a=-2 /:(-3)
a=2/3

b)2b-(1-b)=11-b
2b-1+b=11-b
2b+b+b=11+1
4b=12 /:4
b=3


c)2/5(x-2)=x+4 /*5
2x-4=5x+20
2x-5x=20+4
-3x=24 /:(-3)
x=-8

d)3y-2(y-1)=-6
3y-2y+2=-6
y=-6-2
y=-8

e)3(3-5y)=90-5(3y-2)
9-15y=90-15y+10
-15y+15y=90+10-9
0=91

Answer 2

A) 2(5a-3)-a-4(3a-2)=0
10a-6-a-12a+8=0
-3a+2=0
-3a=-2 |:(-3)
a=⅔

b)2b-(1-b)=11-b
2b-1+b=11-b
3b+b=11+1
4b=12 |:4
b=3

c)2/5(x-2)=x+4
⅖x-⅘=x+4
⅖x-x=4+⅘
-⅗x=4⅘ |:(-⅗)
x=²⁴/₅*(-⁵/₃)
x=8*(-1)
x=-8

d)3y-2(y-1)=-6
3y-2y+2=-6
y=-6-2
y=-8

e)3(3-5y)=90-5(3y-2)
9-15y=90-15y+10
-15y+15y=90+10-9
0=91 <-równanie sprzeczne