Please help me solve 3x + 4y =15 and 3x - y = 30 it is for Algebra I

Step-by-step explanation:

Given the simultaneous equation

3x+4y=15. Equation 1

3x-y=30. Equation 2

Using elimination method

Sutract equation 2 from 1

Then, will have

3x-3x+4y--y=15-50. -×-=+

4y+y=-15

5y=-15

Divide Both sides by 5

y=-15/5

y=-3

From equation 2

3x-y=30

3x--3=30

3x+3=30

3x=30-3

3x=27

Divide both side by 3

x=27/3

x=9

Then, x=9 and y=-3

answer: 80,000

step-by-step explanation:

the population doubles every day.

10,000*2=20,000 day 4

20,000*2=40,000 day 5

40,000*2=80,000 day 6

answer: 8

step-by-step explanation: if you add the possibilities 5 different flavor and 3 different sizes 5+3=8