6 H + 2 J = 28
7 H + 3 J = 36
Fill in the blanks.
- 1 H + 1 J = _____
- 1 H = _____
- 1 J = _____
(a)
6 H + 2 J = 28 --- (1)
7 H + 3 J = 36 --- (2)
(2) - (1)
(7 H + 3 J) - (6 H + 2 J) = 36 - 28
7 H - 6 H + 3 J - 2 J = 8
1 H + 1 J = 8 --- (3)
1 H + 1 J = 8
(b)
Make J the same.
LCM of 1 and 2 = 2
(3) x 2
2 H + 2 J = 16 --- (4)
(1) - (4)
(6 H + 2 J) - (2 H + 2 J) = 28 - 16
6 H - 2 H + 2 J - 2 J = 12
4 H = 12
1 H = 12 ÷ 4 = 3
(c)
Substitute 1 H = 3 into (3).
1 H + 1 J = 8
3 + 1 J = 8
1 J = 8 - 3 = 5
Answer(s): (a) 8; (b) 3; (c) 5