5 V + 2 W = 24
6 V + 3 W = 30
Fill in the blanks.
- 1 V + 1 W = _____
- 1 V = _____
- 1 W = _____
(a)
5 V + 2 W = 24 --- (1)
6 V + 3 W = 30 --- (2)
(2) - (1)
(6 V + 3 W) - (5 V + 2 W) = 30 - 24
6 V - 5 V + 3 W - 2 W = 6
1 V + 1 W = 6 --- (3)
1 V + 1 W = 6
(b)
Make W the same.
LCM of 1 and 2 = 2
(3) x 2
2 V + 2 W = 12 --- (4)
(1) - (4)
(5 V + 2 W) - (2 V + 2 W) = 24 - 12
5 V - 2 V + 2 W - 2 W = 12
3 V = 12
1 V = 12 ÷ 3 = 4
(c)
Substitute 1 V = 4 into (3).
1 V + 1 W = 6
4 + 1 W = 6
1 W = 6 - 4 = 2
Answer(s): (a) 6; (b) 4; (c) 2