<span>These ones are correct:
Multiply the value of the first variable by one of the original equations to solve for the second variable.
</span><span>Solve for one of the variables
</span><span>Substitute the value of the known variable into one of the original equations to solve for the unknown variable.</span>
So we are trying to find this red line's length.
We can either find it directly, or use the blue line firs, and then use it as a leg for the green triangle.
So the blue leg is a hypotenuse for two of the edges. So:

from the Pythagorean Theorem
OR

Which works out to:

So now that we have that, using the Pythagorean Theorem again gives:


So the length of the red line is found that way.
But wait! There's more!
As it turns out, the red line can be found with an easier way that works with cubes and boxes (cuboids). It's really easy:

Where a, b, and c are all 10m, and d is the red line. This greatly reduces the math:

which gives the same answer as above, which you can see.
2.45kg
First you calculate the price per kg as follows:
If it’s $20 for 12.25 kg, the price per kg is $20/12.25=$1.63 per kg
If you have $4, you can figure out what weight you can get by taking $4/the price per kg, so $4/$1.63, which is 2.45 kg.
Answer:
Step-by-step explanation:
since -1≤sin2x≤1 no x values would satisfy the equation
Answer:
the answer is differently C