Câu 2:

1:=>1,3x=-1,31

=>x=-131/130

2: =>\(\left(4.5-2x\right)=\dfrac{11}{14}:\dfrac{-11}{7}=\dfrac{-1}{2}=-0.5\)

=>2x=5

=>x=5/2

7x-2x=6 mũ 2 +44:11

5x=36+4

5x=40

x=40:5=8

Câu 1:

\(=\dfrac{21}{31}+\dfrac{1}{3}-\dfrac{44}{53}+\dfrac{10}{31}-\dfrac{9}{53}=\dfrac{1}{3}\)

Câu 2:

1: =>1,3x=-1,31

=>130x=-131

=>x=-131/130

2: =>(4,5-2x)=11/14:(-11/7)=-7/14=-1/2=-0,5

=>2x=5

=>x=5/2

1/ -7264 + (1543 + 7264)
=-7264 + 1543 + 7264=1543
2/ (144 – 97) – 144

=144-97-144=-97

3/ (-145) – (18 – 145)(Vì có dấu trừ ở trước ngoặc nên p đổi dấu)

=-145-18+145=-18

4/ 111 + (-11 + 27)

=111-11+27=137

1/ -7264 + (1543 + 7264)
=-7264 + 1543 + 7264=1543
2/ (144 – 97) – 144
=144-97-144=-97
3/ (-145) – (18 – 145)(Vì có dấu trừ ở trước ngoặc nên p đổi dấu)
=-145-18+145=-18
4/ 111 + (-11 + 27)
=111-11+27=137

a,  -3/4 + 3/7 + -1/4 + 4/9 + 4/7

=\(\left(\frac{-3}{4}+\frac{-1}{4}\right)+\left(\frac{3}{7}+\frac{4}{7}\right)+\frac{4}{9}\)

=\(-1+1+\frac{4}{9}\)

=\(\frac{4}{9}\)

b, -7/9 x 4/11 + -7/9 x 7/11 + 5 và 7/9 

\(=\frac{7}{9}x\frac{-4}{11}+\frac{7}{9}x\frac{-7}{11}+5x\frac{7}{9}\)

\(=\frac{7}{9}x\left(\frac{-4}{11}+\frac{-7}{11}+5\right)\)

\(=\frac{7}{9}x4\)

\(=\frac{28}{9}\)

c, ( 21/31 + 2013/6039 ) - ( 44/53 - 10/31) - /53

\(\left(\dfrac{21}{31}+\dfrac{-16}{7}\right)+\left(\dfrac{44}{53}+\dfrac{10}{31}\right)+\dfrac{9}{53}.\)

\(\dfrac{21}{31}-\dfrac{16}{7}+\dfrac{44}{53}+\dfrac{10}{31}+\dfrac{9}{53}=\left(\dfrac{21}{31}+\dfrac{10}{31}\right)+\left(\dfrac{44}{53}+\dfrac{9}{53}\right)-\dfrac{16}{7}=1+1-\dfrac{16}{7}=\dfrac{-2}{7}.\)

Tính

\(\left(\frac{21}{31}+\frac{2013}{6039}\right)-\left(\frac{44}{53}-\frac{10}{31}\right)-\frac{9}{53}\)

\(=\frac{21}{31}+\frac{1}{3}-\frac{44}{53}+\frac{10}{31}-\frac{9}{53}\)

\(=\left(\frac{21}{31}+\frac{10}{31}\right)+\left(-\frac{44}{53}-\frac{9}{53}\right)+\frac{1}{3}\)

\(=1+\left(-1\right)+\frac{1}{3}=0+\frac{1}{3}=\frac{1}{3}.\)

X-(44-x)=-144

X-44+X  =-144

X+X-44=-144

Xx2=-144+44

Xx2=-100

X=-100:2

X=-50

x-(44-x)=-144

x-44+x=-144

2x-44=-144

2x=-144+44

2x=-100

x=-100:2

x=-50

vậy x=-50

k cho tui nhé