How do you evaluate #3x^2-4y^2# if #x=5# and #y=3#?

1 Answer
Jun 7, 2017

The answer is #39#.

Explanation:

So, we start with the original problem:

#3x^2-4y^2#

Then we substitute the given #x# and #y# values into the expression:

#3(5)^2-4(3)^2#

Now, according to the order of operations, we simplify the exponential powers first, thus, reducing the expression to this:

#3(25)-4(9)#

Then, we use the order of operations again and do the multiplication next:

#75-36#

We then use the order of operations a final time and finish off the expression with subtraction:

#39#