1. y = 2/3x - 5
2. 4x - 6y = 30
Divide 2. by 2
3. 2x - 3y = 15
Substitute 1. into 3.
4. 2x - 3(2/3x - 5) = 15
5. 2x - 2x + 15 = 15
6. 15 = 15
False. There are an infinite number of solutions.
The band has sold 1,890,000 copies or 1.89 x 10^6
For this case we have:
way 1:
Common factor 3 in the expression:
Way 2:
Write the number 12 as the sum of 4 times 3:

Then, for associative property:
35/100= x/80 x=28 8/100=x/5 x=0.4 50/100=x/125 x=62.5 12/100=48/x x=400