Question

Va rog am nevoie urgent ​

Answer 1

Răspuns:

Explicație pas cu pas:

8.

a) 5x-21=2x⇒5x-2x=21  ⇒3x=21  ⇒x=7

b) 7x+48=-x  ⇒7x+x=-48  ⇒8x=-48  ⇒x=-6

c) 30-3x=2x  ⇒30=2x+3x  ⇒30=5x  ⇒x=6

d) -x+56=6x  ⇒56=6x+x  ⇒56=7x  ⇒x=8

e) 42-x=-7x  ⇒42=-7x+x  ⇒42=-6x  ⇒x=-7

f) -x-27=2x  ⇒-27=2x+x  ⇒-27=3x  ⇒x=-9

9.

a) 4x-6=2x-14  ⇒4x-2x=6-14  ⇒2x=-8  ⇒x=-4

b) 7x+15=4x-6  ⇒7x-4x=-6-15  ⇒3x=-21  ⇒x=-7

c) 8x-5=4x-17  ⇒8x-4x=5-17  ⇒4x=-12  ⇒x=-3

d) 10-2x=3x-15  ⇒10+15=3x+2x  ⇒25=5x  ⇒x=5

e) 13-7x=23-2x  ⇒13-23=7x-2x  ⇒-10=5x  ⇒x=-2

f) 39-9x=21-3x  ⇒39-21=9x-3x  ⇒18=6x  ⇒x=3

Answer 2

Răspuns:

8)

a) 5x-21=2x=> 5x-2x=21=>3x=21/:3=> x=21:3 => x:7

b)7x+48= -x => 7x+×=48 => 8x=48/:8 => x= 48: 8 => x =6

c) 30-3x=2x => (-3x)-2x = 30 => 1x=30/:1=> x= 30:1 => x= 30

d)-x+56=6x => -x-6x = 56 => -5x=56/:(-5) => x= 56: (-5)=> x=11,2

e)42-x=-7x => -x+7x=42 => 8x=42 /:8 => x=42:8=> x=5,25

f) -x-27=2x => -x-2x=27=> 3x=27/:3=> x=27:3=> x=9

9)

a)4x-6=2x-14=> 4x-2x=14+6=> 2x=20/:2=> x=20:2 => x= 10

b)7x+15=4x-6=> 7x-4x=6-15=> 3x= -9/:3=> x= -9:3 => x= -3

c)8x-5=4x-17 => 8x-4x=17-5=> 4x= 12/:4=> x= 12:4 => x= 3

d)10-2x=3x-15 => -2x-3x = 15-10 => 5x=5/:5=> x=5:5 =>x=0

e)13-7x=23-2x=> 7x-2x = 23-13=> 5x=10/:5=> x=10:5=> x=2

f)39-9x=21-3x => 9x-3x= 39-21 => 6x= 18/:6 => x= 18:6=> x=3

Sper ca te-am ajutat si sper sa înțelegi❤