- Ejercicio 15
Sumar
- m, n
m+n
- m, -n
m+(
–n
)
=m–n - -3a, 4b
–3a+4b
- 5b, -6a
5b+(
–6a
)
=5b–6a - 7, -6
7+(
–6
)
=7–6=1 - -6, 9
–6+9=3
- -2x, 3y
–2x+3y
- 5mn, -m
5mn+(
–m
)
=5mn–m - 5a, 7a
5a+7a=12a
- -8x, -5x
–8x+(
–5x
)
=–8x–5x=–13x - -11m, 8m
–11m+8m=–3m
- 9ab, -15ab
9ab+(
–15ab
)
=9ab–15ab=–6ab - -xy, -9xy
–xy+(
–9xy
)
=–xy–9xy=–10xy - mn, -11mn
mn+(
–11mn
)
=mn–11mn=–10mn -
1
2
a,–
2
3
b
1
2
a+(–
2
3
b
)
=
1
2
a–
2
3
b -
3
5
b,
3
4
c
3
5
b+
3
4
c
-
1
3
b,
2
3
b
1
3
b+
2
3
b=
b+2b
3
=
3
b
3
=b
-
–
1
2
xy,–
1
2
xy
–
1
2
xy+(–
1
2
xy
)
=–
1
2
xy–
1
2
xy=
–xy–xy
2
=–
2
xy
2
=–xy -
–
3
5
abc,–
2
4
abc
–
3
5
abc+(–
2
4
abc
)
=–
3
5
abc–
2
4
abc=
–12abc–10abc
20
=–
abc
=–
11abc
5
-
–4
x
2
y,
3
8
x
2
y
–4
x
2
y+
3
8
x
2
y=
–32
x
2
y+3
x
2
y
8
=–
29
8
x
2
y
-
3
8
mn,–
3
4
mn
3
8
mn+(–
3
4
mn
)
=
3
8
mn–
3
4
mn=
3mn–6mn
8
=–
3
8
mn - a, b, c
a+b+c
- a, -b, c
a+(
–b
)
+c=a–b+c - a, -b, 2c
a+(
–b
)
+2c=a–b+2c - 3m, -2n, 4p
3m+(
–2n
)
+4p=3m–2n+4p -
a
2
,–7ab,–5
b
2
a
2
+(–7ab
)
+(–5
b
2
)=
a
2
–7ab–5
b
2
-
x
2
,–3xy,–4
y
2
x
2
+(–3xy
)
+(–4
y
2
)=
x
2
–3xy–4
y
2
-
x
3
,–
x
2
y,6
x
3
+(–
x
2
y
)
+6=
x
3
–
x
2
y+6
-
2a,–b,3a
2a+(–b
)
+3a=
2a–b+3a=5a–b
-
–m,–8n,4n
–m+(–8n
)
+4n=
–m–8n+4n=–m–4n
-
–7a,8a,–b
–7a,8a,–b
=
–7a+8a+(–b
)
=–7a+8a–b=a–b -
1
2
x,
2
3
y,–
3
4
x
1
2
x+
2
3
y+(–
3
4
x
)=
1
2
x+
2
3
y–
3
4
x
=
x–3x
4
+
2
3
y
=
–
4
x
4
+
2
3
y
=
–x+
2
3
y
-
–
3
5
m,–m,–
3
8
mn
–
3
5
m+(–m
)
+(–
3
8
mn
)=
–
3
5
m–m–
3
8
mn
=
–3m–5m
5
–
3
8
mn
=
–
8
5
m–
3
8
mn
-
–
7
2
,5ab,3
b
2
,–
a
2
–
7
2
+5ab+3
b
2
+(–
a
2
)=
–
7
2
+5ab+3
b
2
–
a
2
-
–7m
n
2
,–5m,17m
n
2
,–4m
–7m
n
2
+(–5m
)
+17m
n
2
+(–4m
)=
–7m
n
2
–5m+17m
n
2
–4m
=
10m
n
2
–9m
-
x
3
,–8
x
2
y,5,–7
x
3
,4
x
2
y
x
3
+(–8
x
2
y
)
+5+(–7
x
3
)
+4
x
2
y=
x
3
–8
x
2
y+5–7
x
3
+4
x
2
y
=
–6
x
3
–4
x
2
y+5
-
5
x
2
,9xy,–6xy,7
y
2
,–
x
2
5
x
2
+9xy+(–6xy
)
+7
y
2
+(–
x
2
)=
5
x
2
+9xy–6xy+7
y
2
–
x
2
=
4
x
2
+3xy+7
y
2
-
–8
a
2
b,5a
b
2
,–
a
2
b,–11a
b
2
,–7
b
3
–8
a
2
b+5a
b
2
+(–
a
2
b
)
+(–11a
b
2
)
+(–7
b
3
)=
–8
a
2
b+5a
b
2
–
a
2
b–11a
b
2
–7
b
3
=
–9
a
2
b–6a
b
2
–7
b
3
-
m
3
,–8
m
2
n,7m
n
2
,–
n
3
,7
m
2
n
m
3
+(–8
m
2
n
)
+7m
n
2
+(–
n
3
)
+7
m
2
n=
m
3
–8
m
2
n+7m
n
2
–
n
3
+7
m
2
n
=
m
3
–
m
2
n+7m
n
2
–
n
3
-
1
2
a,
2
3
b,–
1
4
a,
1
5
b,–6
1
2
a+
2
3
b+(–
1
4
a
)
+
1
5
b+(–6
)=
1
2
a+
2
3
b–
1
4
a+
1
5
b–6
=
2a–a
4
+
10b+3b
15
–6
=
a
4
+
13b
15
–6
-
a,–3b,–8c,4b,–a,8c
a+(–3b
)
+(–8c
)
+4b+(–a
)
+8c=
a
–3b–
8c
+4b–
a
+
8c
=
b
-
m
3
,–4
m
2
n,5
m
3
,–7m
n
2
,–4
m
2
n,–5
m
3
m
3
+(–4
m
2
n
)
+5
m
3
+(–7m
n
2
)
+(–4
m
2
n
)
+(–5
m
3
)=
m
3
–4
m
2
n+5
m
3
–7m
n
2
–4
m
2
n–5
m
3
=
m
3
–8
m
2
n+
5
m
3
–7m
n
2
–
5
m
3
=
m
3
–8
m
2
n–7m
n
2
-
9x,–11y,–x,–6y,4z,–6z
9x+(–11y
)
+(–x
)
+(–6y
)
+4z+(–6z
)=
9x–11y–x–6y+4z–6z
=
8x–17y–2z
-
6
a
2
,–7
b
2
,–11,–5ab,9
a
2
,–8
b
2
6
a
2
+(–7
b
2
)
+(–11
)
+(–5ab
)
+9
a
2
+(–8
b
2
)=
6
a
2
–7
b
2
–11–5ab+9
a
2
–8
b
2
=
15
a
2
–5ab–15
b
2
–11
-
–
x
2
y
2
,–5x
y
3
,–4
y
4
,7x
y
3
,–8,
x
2
y
2
–
x
2
y
2
+(–5x
y
3
)
+(–4
y
4
)
+7x
y
3
+(–8
)
+
x
2
y
2
=
–
x
2
y
2
–5x
y
3
–4
y
4
+7x
y
3
–8+
x
2
y
2
=
2x
y
3
–4
y
4
–8
-
3a,
1
2
b,–4,–b,–
1
2
a,6
3a+
1
2
b+(–4
)
+(–b
)
+(–
1
2
a
)
+6=
3a+
1
2
b–4–b–
1
2
a+6
=
6a–a
2
+
b–2b
2
+2
=
5a
2
–
b
2
+2
-
1
2
x
2
,
2
3
xy,
5
6
y
2
,–
1
3
xy,
3
4
x
2
,–
5
6
y
2
1
2
x
2
+
2
3
xy+
5
6
y
2
+(–
1
3
xy
)
+
3
4
x
2
+(–
5
6
y
2
)=
1
2
x
2
+
2
3
xy+
5
6
y
2
–
1
3
xy+
3
4
x
2
–
5
6
y
2
=
2
x
2
+3
x
2
4
+
2xy–xy
3
=
5
x
2
4
+
xy
3
-
5
a
x
,–6
a
x+1
,8
a
x+2
,
a
x+1
,5
a
x+1
,–5
a
x
5
a
x
+(–6
a
x+1
)
+8
a
x+2
+
a
x+1
+5
a
x+1
+(–5
a
x
)=
5
a
x
–
6
a
x+1
+8
a
x+2
+
a
x+1
+
5
a
x+1
–
5
a
x
=
8
a
x+2
-
3
4
x
2
,–
2
3
xy,
1
3
y
2
,–
1
3
xy,
x
2
,5
y
2
3
4
x
2
+(–
2
3
xy
)
+
1
3
y
2
+(–
1
3
xy
)
+
x
2
+5
y
2
=
3
4
x
2
–
2
3
xy+
1
3
y
2
–
1
3
xy+
x
2
+5
y
2
=
3
x
2
+4
x
2
4
+
–2xy–xy
3
+
y
2
+15
y
2
3
=
7
x
2
4
–
xy
3
+
16
y
2
3
-
3
4
a
2
b,
1
2
a
b
2
,–
1
4
a
2
b,
1
2
a
b
2
,
a
2
b,–
5
6
a
b
2
3
4
a
2
b+
1
2
a
b
2
+(–
1
4
a
2
b
)
+
1
2
a
b
2
+
a
2
b+(–
5
6
a
b
2
)=
3
4
a
2
b+
1
2
a
b
2
–
1
4
a
2
b+
1
2
a
b
2
+
a
2
b–
5
6
a
b
2
=
3
a
2
b–
a
2
b+4
a
2
b
4
+
3a
b
2
+3a
b
2
–5a
b
2
6
=
a
2
b
+
a
b
2
6
=
3
a
2
b
2
+
a
b
2
6