Lesson 5-14 for exercise sets. &KDSWHU
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To solve a subtraction equation with positive and negative fractions,
apply the Addition Property of Equality.
Solve: n
n Add to both sides to isolate n.
n Rename as fractions with a common denominator, then add.
n
Check: n
Substitute for n, then subtract.
Tr u e
To solve an addition or subtraction equation with mixed numbers,
rename so the fraction parts have like denominators.
7
8
3
8
1
2
1
2
4
8
(^1) ?
2
7
8
?
(^12)
1
2
3
8
3
8
7
8
3
8
4
8
3
8
3
8
3
8
1
2
3
8
1
2
Remember:
Addition Property of Equality
If a b, then a c b c.
Solve for x. Then use substitution to check.
1.x 2.y() 3. m
- x 5.x() 6.x 7 13
7.Discuss and Write What steps would you take to solve for k?
k
3
5
1
2
3
10
4
5
1
2
7
10
3
4
1
12
3
10
3
5
1
4
3
8
1
2
3
4
5
8
1
4
Think
104 10 4 ^2225
Think
84 8 4 ^4412
Solve:n 4 17
n 4 4 17 4 Add 4 to both sides to isolate n.
n 17 4 Rename, using a common denominator, then add.
n 21
Check:n 4 17
21 417 Substitute 21 for n.
17 17 Subtract.
1725 1725 Tr u e
2
5
(^4) ?
10
7
10
2
5
(^3) ?
10
7
10
2
5
3
10
7
10
3
10
4
10
3
10
3
10
2
5
3
10
3
10
2
5
3
10