x = 3
2x + y - z = 3 → (1)
- x + y + 2z = 0 → (2)
3x + 2y + z = 9 → (3)
we require to eliminate the y and z terms from the equations
(1) + (3) : 5x + 3y = 12 → (4)
multiply (1) by 2
4x +2y - 2z = 6 → (5)
(2) + (5) : 3x + 3y = 6 → (6)
(4) - (6) : 2x = 6 ⇒ x = 3
15. 1hour 7minutes and 5seconds
Well I don't know !
Let's take a look and see:
The idea is that there could be more than one way
for a roll of the dice to land with the same number.
-- If the sum is from 1-4, you get the point.
There are 6 different ways for a roll of the dice to come up 1-4.
-- If the sum is from 5-8, Adam gets the point.
There are 20 different ways for a roll of the dice to come up 5-8.
-- If the sum is 9-12, Lana gets the point.
There are 10 different ways for a roll of the dice to come up 9-12.
-- The game is not fair to all three of you.
-- Lana has a distinct advantage over you.
-- Adam has a big advantage over Lana.
-- Adam has an even bigger advantage over you.
-- You are at a big disadvantage. (Notice that one of your
numbers ... 1 ... can never come up unless one of the dice
falls off of the table.)
_______________________________
Here's how to figure it:
Ways to roll a 2:
1 ... 1
Ways to roll a 3:
1 ... 2
2 ... 1
Ways to roll a 4:
1 ... 3
2 ... 2
3 ... 1
Ways to roll a 5:
1 ... 4
2 ... 3
3 ... 2
4 ... 1
Ways to roll a 6:
1 ... 5
2 ... 4
3 ... 3
4 ... 2
5 ... 1
Ways to roll a 7:
1 ... 6
2 ... 5
3 ... 4
4 ... 3
5 ... 2
6 ... 1
Ways to roll an 8:
2 ... 6
3 ... 5
4 ... 4
5 ... 3
6 ... 2
Ways to roll a 9:
3 ... 6
4 ... 5
5 ... 4
6 ... 3
Ways to roll a 10:
4 ... 6
5 ... 5
6 ... 4
Ways to roll 11:
5 ... 6
6 ... 5
Ways to roll 12:
6 ... 6
Answer: Marcie jogged twice as many miles this week as she jogged last week
Step-by-step explanation:
Refer to the diagram shown below.
w = 6 7/8 in = 6.875 in, the width of each device.
d = 3 1/2 in = 3.50 in, the space between teo devices.
The total space needed is
D = 4(w+d) + w
= 5w + 4d
= 5*6875 + 4*3.5
D = 48.375 in or 48 3/8 in
Answer: 48 3/8 inches or 48.375 inches
