1. EJERCICIO 9 y 10 DEL LIBRO DE BALDOR
EJERCICIO 9 (consta de 40 ejercicios)
9a-
1. 9a-3a+5a=
9a-3a=6a
6a+5a=11a
=
8x+9x-
2. -8x+9x-x=
-8x+9x=x
x-x=0
=
12mn-23mn-
3. 12mn-23mn-5mn=
12mn-23mn=-11mn
-11mn-5mn=-16mn
=−
x+19x-
4. -x+19x-18x=
-x+19x=18x
18x-18x=0
=
19m-
5. 19m-10m+6m=
19m-10m=9m
9m+6m=15m
=

2. 6.-11ab-15ab+26ab=
6.-11ab-
-11ab-15ab=-26ab
-26ab+26ab=0
=
.− + − =
−5!" +9! " = 4! "
4! " −35! " = −31! "
=−
&$ '$ '$
#. −$% − + =
−24! "'( −15! "'( = −39! "'(
−39! "'( +39! "'( = 0
=
$
9. ) + ) − ) =
2 1 3
+ =
3 3 3
R= ) − )
10.-
10.- − + − =
% $
+ - - &-(',&-/ &-0
−, + . − ( = (/
= (/
&
R= $
11. # ²2 + % ²2 − ²2 =
3 1 3+2 5
+ = =
8 4 8 8
R=# ²2 − ²2
a+8a+9a-
12. –a+8a+9a-15a=

3. -1+8+9-15=1
R=a
7ab-11ab+20ab-
13. 7ab-11ab+20ab-31ab=
7ab-11ab+20ab-31ab=-15ab
R=-
R=-15ab
25x²-
14. 25x²-50x²+11x²+14x²=
25-50+11+14=0
R=0
xy-8xy-
15. -xy-8xy-19xy+40xy=
-1-8-19+40=12
R=12xy
7ab+21ab-ab-
16. 7ab+21ab-ab-80ab=
7+21-1-80=-53
R=-
R=-53ab
25xy²+11xy²+60xy²-
17. -25xy²+11xy²+60xy²-82xy²=
-25+11+60-82=-36
R=-36xy²
R=-36xy²
18.-72ax+87ax-
18.-72ax+87ax-101ax+243ax=
-72+87-101+243=157
R=157ax
82bx-71bx-
19. -82bx-71bx-53bx+206bx=
-82bx-71bx-53bx=-206bx
-206bx+206bx= 0
=
20. 105 -464 +58 +301 =

4. 105!+ +58!+ +301!+ = 464!+
464!+ -464!+ = 0
R=0
21. $ x - x + %
x- x=
2345 2 30-20+15-12 = 13
x
1325 2 60 60
1315 3
1115 5 m.c.m= 60
1111
R=
22. y - y + y- $
y=
3 3 6 12 2 4-4+2-1 = 1
3336 2 12 12
3333 3
1111 m.c.m= 12
R= $ )
$ $ $ $
23. 2- 2+ 2- 2=
- 0
563 2 18-5+10 23 − =−
= - +/
533 3 30 30
511 5
111 m.c.m = 30
$
R=−
R= 2
24. - 2$ - 2$ + 2$ - 2$ =
#

5. 5 1
− !7 ( − !7( = −!7 ( + !7( = 0
6 6
3 3
− !7 ( = − !7 (
8 8
R= # 2$
R=−
a+8a-11a+15a-
25. a+8a-11a+15a-75a=
8a+15a= 23a
-11a-75a= -86a
23a-86a = -64ª
R=-
R=-64a
7c+21c+14c-
26. -7c+21c+14c-30c+82c=
21c+14c+82c= 117c
-7c-30c= -37c
117c-37c = 80c
R=80c
mn+14mn-31mn-
27. -mn+14mn-31mn-mn+20mn=
14mn+20mn= 34mn
-mn-31mn-mn= -33mn
34mn-33mn= mn
R=mn
$ $ $ $ $
28. y -7 y - 93 y + 51 y + 48 y=
!( y + 51!( y + 48!( y = 100!( y
- 7!( y - 93!( y = -100!( y
100!( y -100!( y=0
=
29. -a + a –a +a -3a + 6a =

6. -a - a – 3a = -5a
2a + 6a = 8a
8a – 5a=3a
=$
$
30. $ x + x - x + $ x – x=
- ( - -/
(
x++x+(x= 9
x
0 -+
- x–x= x
9 9
10 13 3 1
:− =− =−
6 6 6 2
=−
$
31. -2x + %x + %x + x - x=
+ - ;
.
x + .x + x = .x
, -0
-2x - x = - x
9 9
; -0 -/ ,
x- x =− =−
. 9 -( 9
=−
32. 7 - 30 – 41 -9 + 73 =
7! " + 73! " = 80!"
- 30!" – 41! " -9 !" = -80!"
80! " -80!" =0
=
' ' ' ' '
33. - -7 − − $ + $ =
-! "'- - 7! "'- − 11! "'- − 20! "'- = -39 ! "'-
-39 !"'- 26!"'- = -13!"'-

7. '
R=-
R=-13
34. a + 6a – 20a + 150a – 80a + 31a=
a + 6a + 150a + 31a = 188a
– 20a – 80a =−100!
188! − 100! = 88!
R=88a
35. -9b - 11b -17b – 81b – b + 110b=
-9b - 11b -17b – 81b – b = -119b
-119b + 110b =-9b
R=-
R=-9b
$ $ $ $ $ $
36. - b + 15 b+ b - 85 b - 131 b + 39 b=
15!( b + !( b + 39!( b = 55!( b
-!( b - 85!( b - 131!( b = -217!( b
55!( b -217!( b = -162!( b
$
R=-
R=-162 b
$ $ $ $ $ $
37. #% − − % − +$ + =
84<( : + 231<( : + 165<( : = 480<( :
−501<( : − 604<( : − 715<( : = −1820<( :
480<( : − 1820<( : = −940
$
R= − %
$
#. 2$ + 2$ − 2$ + % 2$ =
%
5 + ( 2 + ( 4 + ( 5 12 24
! 7 + ! 7 + ! 7 = !+ 7 ( + !+ 7 ( + ! + 7 (
6 3 1 6 18 6
5 + ( 12 + ( 24 + ( 15 + ( 12 + ( 72 + ( 99 + (
! 7 + ! 7 + ! 7 = ! 7 + ! 7 + ! 7 = ! 7
6 18 6 18 18 18 18

8. 1 5 2 5 7
− ! + 7 ( − ! + 7 ( = − !+ 7 ( − ! + 7 ( = − !+ 7 (
4 8 8 8 8
99 + ( 7 + ( 5
! 7 − ! 7 = 4 !+ 7 (
18 8 8
R=%
R= # 2$
. % −# + +% −# − + =
40! + 130! + 41! + 16! = 227!
−81! − 83! − 91! = −255!
−255! + 227! = −28!
R=-
R=-28a
% . −$ 2+ $ 2− 2 + #% 2 − 2− 2−$ 2=
=
−21!7 − 60!7 − 31!7 − !7 − 23!7 = −136!7
52!7 + 84!7 = 136!7
136!7 − 136!7 = 0
R=0
EJERCICIO 10 (consta de 20 ejercicios)
1. = − > + = − %>=
=
7a + 6a = 13a
−9b − 4b = −13b
?= =− >
$. = + > − @ − > − @ + $@ − = =
a−a=0
b−b= 0
−c − c = −2c + 2c = 0
R=

9. . A − B− +$ A− − B=
=
5x + 20x = 25x
−11y − y = −12y
−9 − 1 = −10
? = $ A − $B −
%. − C + #D + −C−D− C− =
−6m − m − 6m = −13m
8n − n = 7n
5 − 11 = −6
?=− C+ D−
5. -a+b+2b-2c+3a+2c-3b=
5. -a+b+2b-2c+3a+2c-3b=
-a+3a= 2a
1b+2b-3b=0
-2c+2c=0
R=2a
R=2a
6. -81x+19y-30z+6y+80x+x-25y=
6. -81x+19y-30z+6y+80x+x-25y=
-81x+80x+1=0
19y+6y-25y=0
-30z=-30z
R=-30z
R=-30z
7. 15a2-6ab-8a2+20-5ab-31 $ -ab=
7. 15a 6ab- +20-5ab-31+= ab=
15a2-8a2+a2= 8a2
-6ab-5ab=-11ab-ab= -12ab
20-31=-11
R=8a2-12ab-11
12ab-11

10. 8. -3a+4b-6a+81b-114b+31a-a-b=
3a+4b-6a+81b-114b+31a-
-3a-6a=-9a+31a=22a-1a=21a
4b+81b=85b-114b=-29-1=-30b
R=21a-
R=21a-30b
9. -71a3b-84a4b2+50a3b+84a4b2-45a3b+18a3b=
-71a3b+50a3b=-21a3b-45a3b=-66a3b+18a3b=-48a3b
-84a4b2+84a4b2=0
R=-
R=-48a3b
a+b-c+8+2a+2b-19-2c-3a-
10. -a+b-c+8+2a+2b-19-2c-3a-3-3b+3c=
-1a+2a=a-3a=-2a
b+2b=3b-3b=0
-c-2c=-3c+3c=0
8-19=-11-3=-14
R=-2a-
R=-2a-14
+71mn-
11. m2+71mn-14m2-65mn+m3-m2-115m2+6m3 =
m2-14m2=-13m2-m2=-14m2-115m2=-129m2
71mn-65mn=6mn
m3+6m3=7m3
R=-129m2+6mn+7m3
R=-
12. X4y-x3 y2+x2 y-8x4 y-x2 y-10+x3 y2-7x3 y2-9+21x4 y-y3+50=
X4 y-8x4 y=-7x4 y+21x4 y=14x4 y
-x3 y2+x3y2=0-7x3y2=-7x3y2
x2 y-x2 y=0
-10-9=-19+50=31
-y3=-y3

11. R=14x4 y-7x3y2+31-y3
+31-
' '$ ' ' '$ '$ '
. − 2 − #G − − + %2 − −2 + +G +
'
G =
5! "'- − 5! "'- = 0
−37 "'( + 47 "'( − 7 "'( = 0
−3H "'+ − 8H "'+ + H "'+ + 7H "'+ = 0
−50 − 65 + 90 = −25
R=-
R=-25
'$ ' '$ ' '$ '
%. − − +#− + − + − =
!I'( − 3!I'( + !I'( = −!I'(
−: I'+ + 5: I'+ − 5: I'+ = −: I'+
-5+8-6=-3
'$ '
=− − −
15. 0.3a+0.4b+0.5c-0.6a-0.7b-0.9c+3a-3b-3c=
0.3a+0.4b+0.5c-0.6a-0.7b-0.9c+3a-3b-
0.3a-0.6a+3a=2.7a
0.4b-0.7b-3b=-3.3b
0.5c-0.9c-3c=-3.4c
R=2.7a-3.3b-
R=2.7a-3.3b-3.4c
. + 2+$ − 2− − 2+ − =
$ % % $
1 3 3
! + 2! − ! = 1 !
2 4 4
1 1 17
7 − 37 − 7 = − 7
3 6 6
3 1 1
− =
4 2 4
= + 2+
% %

12. $ $ $
. −$ + − +$ −$
3 ( 1 3
< + <( − 2<( = −1 <(
5 10 10
1 1
−2<J − <J + 2<J = − <J
3 3
$
= −
$
#. − + 2 − 2$ + $ $
− 2 + 2$ − 2$ − $ 2 =
% $ %
1 3 7
2 ! ( − ! ( = 1 !(
3 4 12
1 3 1
!7 − !7 − 2!7 = −2 !7
2 4 4
5 1 1
− b( + b( − b( = −b(
6 6 3
R= =$ − $ => − >$
$ %
$
. . %A $ B + + AB $ − . B − A $ B − . $AB $ + B − =
# %
4 ( 2
x y − x ( y = 0
10 5
31-6=25
3 ( 2 7 (
xy − xy ( = xy
8 10 40
6 + 1 + 7
− y + y = − y+
10 4 20
?=$ + AB $ − B
% $
$ . =C& − >C&$ + =C& − >C&$ − . $=C& + >C&$
$ $
3 K&- 3 K&- 2 K&- 13 K&-
a + a − a = a
25 5 10 25

13. 7 K&( 1 1 1 K&(
− b − bK&( + bK&( = b
50 25 5 50
?= =C& + >C&$
$