5 V + 3 W = 66
6 V + 4 W = 82
Fill in the blanks.
- 1 V = _____
- 1 W = _____
- 5 V + 4 W = _____
(a)
5 V + 3 W = 66 --- (1)
6 V + 4 W = 82 --- (2)
Make W the same.
LCM of 3 and 4 = 12
(1) x 4
20 V + 12 W = 264 --- (3)
(2) x 3
18 V + 12 W = 246 --- (4)
(a)
(3) - (4)
(20 V + 12 W) - (18 V + 12 W) = 264 - 246
20 V - 18 V + 12 W - 12 W = 18
2 V = 18
1 V = 18 ÷ 2 = 9
(b)
Substitute V = 9 into (1).
5 V + 3 W = 66
5 x 9 + 3 W = 66
45 + 3 W = 66
3 W = 66 - 45 = 21
1 W = 21 ÷ 3 = 7
(c)
5 V + 4 W
= 5 x 9 + 4 x 7
= 45 + 28
= 73
Answer(s): (a) 9; (b) 7; (c) 73