List all the multiples of the numbers:
2: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100
5: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100
6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72, 78, 84, 90, 96
9: 9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99
The least common multiple of 2, 5, 6, and 9 is 90.
Answer:
B
Step-by-step explanation:
x + 3y = 7 → (1)
3x + 2y = 0 → (2)
Multiplying (1) by - 3 and adding to (2) will eliminate x
- 3x - 9y = - 21 → (3)
Add (2) and (3) term by term to eliminate x
0 - 7y = - 21
- 7y = - 21 ( divide both sides by - 7 )
y = 3
Substitute y = 3 into either of the 2 equations and solve for x
Substituting into (1)
x + 3(3) = 7
x + 9 = 7 ( subtract 9 from both sides )
x = - 2
solution is (- 2, 3 ) → B
