5 V + 3 W = 34
6 V + 4 W = 42
Fill in the blanks.
- 1 V + 1 W = _____
- 1 V = _____
- 1 W = _____
(a)
5 V + 3 W = 34 --- (1)
6 V + 4 W = 42 --- (2)
(2) - (1)
(6 V + 4 W) - (5 V + 3 W) = 42 - 34
6 V - 5 V + 4 W - 3 W = 8
1 V + 1 W = 8 --- (3)
1 V + 1 W = 8
(b)
Make W the same.
LCM of 1 and 3 = 3
(3) x 3
3 V + 3 W = 24 --- (4)
(1) - (4)
(5 V + 3 W) - (3 V + 3 W) = 34 - 24
5 V - 3 V + 3 W - 3 W = 10
2 V = 10
1 V = 10 ÷ 2 = 5
(c)
Substitute 1 V = 5 into (3).
1 V + 1 W = 8
5 + 1 W = 8
1 W = 8 - 5 = 3
Answer(s): (a) 8; (b) 5; (c) 3
