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) :)
1,54 3,8 6,9
multiply the pairs of numbers
Answer:
an = 80. 2^(n-5)
Step-by-step explanation:
r = a6/a5 =160/80 = 2
an = a5. r^(n-5)
= 80. 2^(n-5)
Answer:
positive
negetive
negative
positive
Step-by-step explanation:
multiplication of of negetive values is positive
multiplication of positive value and negetive value is negetive
We can write it down as:
5 = 2x - 3 / + 3 (both sides)
8 = 2x / : 2 (both sides)
x = 4
Bob has 4 CDs. Let's check it:
5 = 2 * 4 - 3
5 = 8 - 3
5 = 5
Correct.
