Answer:
Step-by-step explanation:
The question got caught off. Can't read any of the other examples. I can tell you though that ice melting is a physical change, not a chemical change.
My guess is that you're doing the Law of Cosines? You have everything you need for that except the angle theta, which is the thing you need to find. It's set up like this: (8)^2 = (10)^2 + (5)^2 -[2(10)(5)cos A] I used A instead of theta. Doing that math, you have: 64 = 100 + 25 -[ 100 cos A]; 64 = 125 - 100 cos A;
-61 = - 100 cos A; -61 / -100 = cos A; .61 = cos A. Now use your inverse function on your calculator to find cos^-1(.61) and that equals 52.4
Answer:
(6,0)
Step-by-step explanation:
The given system has equations:


Multiply the top equation by 2 to get:


Subtract the top equation form the bottom equation to get:



Put y=0 into 


Therefore the solution is (6,0)
Answer:
20 minutes
Step-by-step explanation:
Remember that

we know that
Hector has 3/4 hour to spend his homework
Convert to minutes

so
1) He wants to spend 1/3 of this time on math homework
To find out the time on math homework, multiply 45 minutes by 1/3

2) He wants to spend 10 minutes of his time on reading homework
3) He wants to spend the remaining time on science homework
The time spend on math homework plus the time spend reading homework, plus the time spend on his science homework must be equal to 45 minutes
Let
x ----> the time spend on his science homework

Solve for x

What do u need help on? It gives u the answer which is X=10/3