For this case, what you should keep in mind are the following considerations:
1) Rewrite the expressions correctly using the properties of the exponents: Addition, multiplication, division, subtraction and negative exponents.
2) Simplify the expression as much as possible.
Answer:
See attached image.
Answer:
x=11
z=16
Step-by-step explanation:
5x+3z=70
3x+4z=64
2x-z=6
z=2x-6
5x+3(2x-6)=70
11x=88
x=11
z=2(11)-6
=16
Answer:

Step-by-step explanation:
Since this is a 30-60-90 triangle, we know that the sides have the following characteristic:
The side opposite to 30 degree angle: n
The side opposite to 60 degree angle: 
The side opposite to 90 degree angle: 2n
Since we know that 7 is opposite to 30-degree, and x is opposite to 60 degree, than we know that x = 
Yes because it is just milk and a substance in the milk