You can start by subtracting different equations from each other.
3x + 2y + 3z = 1
subtract
3x + 2y + z = 7
2z = -6
divide by 2
z = -3
add the following two expressions together:
3x + 2y + z = 7
3x + 2y + 3z =1
6x + 4y + 4z = 8
subtract the following two expressions:
6x + 4y + 4z = 8
5x + 5y + 4z = 3
x - y = 5
^multiply the whole equation above by 3
3x - 3y = 15
subtract the following two expressions:
3x - 3y = 15
3x + 2y = 10
-5y = 5
divide each side by -5
y=-1
take the following expression from earlier:
x - y = 5
substitute y value into above equation
x - - 1 = 5
2 negatives make a positive
x + 1 = 5
subtract 1 from each side
x = 4
Therefore x = 4, y = -1, z = -3
I checked these with all 3 equations and they worked :)
(it's quite complicated, comment if you don't understand anything) :)
Decimal places mean we just start counting immediately after the decimal point, so:
2dp: 0.00
1dp: 0.0
Significant figures, we start counting starting at the first non zero number
So we start counting at the 9, therefore:
2sf: 0.00097
3sf: 0.000965
Answer:
Step-by-step explanation:
Current Weight Weight after adding Marbles
Giulio: 2x 2x + 10
Jim: x x + 5
You didn't post the options so hopefully you can determine the answer based on the info I provided above.
I looked it up and it said it was c