1 )
1st and 2nd equation (multiply 1st by -2 ):
-2x - 10 y + 8 z = 20
2 x - y + 5 z = -9
---------------------------
- 11 y + 13 z = 11 / * ( -20 )
1st and 3rd:
- 2 x - 10 y + 8 z = 20
2 x - 10 y - 5 z = 0
-----------------------------
- 20 x + 3 z = 20 / * 11
----------------------------------
220 y - 260 z = -220
- 220 y + 33 z = 220
------------------------------
z = 0, y = -1, x = - 5
2 )
2 x - y + 5 = -4
- 2 x + 3 y - 5 = - 10
Substitution: y = 2 x + 9
- 2 x + 3(2 x + 9 ) = -5
4 x = - 32, x = -8, y = -7, z = 5
3 )
x + y + z = 11
1.5 x+3 y +1.5 z = 21
x = 2 y
------------------------
3 y + z = 11 / * (-2)
6 y + 1.5 z = 21
------------------------
- 6 y - 2 z = -22
6 y + 1.5 z = 21
------------------------
-0.5 z = -1, z = 2, y = 3, z = 6
Answer: the store used 6 pounds of peanuts, 3 pounds of almonds and 2 pounds of raisins.
The answer to this question using the quadratic formula is x= -1+3√5/2 and x=-1-3<span>√5/2
</span>that is a square root, or, 3 times the square root of 5 ALL over 2, except for the 1. Same with the other one.
All the rectangle are square if length becomes equal to breath !
Answer: Choice A) 
==================================================
Work Shown:
When going from 234 to 9*26, the idea here is to factor where one factor is the largest perfect square possible. That way we can use the rule 
to break up the root and simplify.
Answer: 4
Step-by-step explanation:
Because %s can be expressed as fractions over 100, because 90 is 70% of x, 70% is 70% of 100. Thus, 90/x = 70/100.
<em>Hope it helps <3</em>
