It's pretty simple! So it looks like you are learning proportions. You would cross multiply to achieve your answer.
First, let's do your first problem:
2 12
--- = ----
5 n
You would take 5 and multiply it by 12 and get 60! Then you would do the same with 2 times n, giving you 2n (because you do not know what n represents YET.)
Now you should have this:
60=2n OR 2n=60
We must isolate our variable, in order to do that, get rid of two! But how? You would do this by dividing 2n by 2. Yet in equations, when you do something to one side, you must do it to the other because they must be EQUAL! (hence the "equa-" in equation)
2n=60
--- ---
2 2 DIVIDE 2 into 60
----------
n= 30 Simplify!
Your final answer for the first question is n= 30!
Answer:
here are two possible solutions
Step-by-step explanation:
Answer:

Step-by-step explanation:
There's no need of hypotenuse for finding area of the triangle. To find the area of a triangle ,
Formula is =
Base of the triangle = 10 cm
Height of the traingle = 3 cm
Area of the triangle = 
The triangle below has a perimeter of 27\text{ cm}27 cm27, start text, space, c, m, end text.
What is the length of one side of the triangle?
All 333 sides are the same length.
Answer:
The second choice is the correct one.
Step-by-step explanation:
20x^4 - 45x^2
GCF is 5x^2, so the factors are:
5x^2( 4x^2 - 9)
Now 4x^2 - 9 is the differencr of 2 squares:
4x^2 - 9 = (2x + 3)(2x - 3)>