Find the limit by direct substitution.

A. lim x-> 5
square root cubed of x^2 -2x - 23. I replaced all of the x's with 5 and got -2.

B. lim x-> -2
(4x^2 - 7x) / (6x + 10). I replaced all of the x's with -2 and got -15. Go to picturetrail and type in rowdy33. It's problems 3a and 3b. Thanks.

A. How did you get -2? Can you show your work?

I get (5)^2-2(5)-23=-8

B. -15 is Correct.

To find the limit by direct substitution, you need to substitute the value of x directly into the expression and evaluate it. Let's work through both examples:

A. lim x-> 5
√(x^2 - 2x - 23)

To find the limit, substitute x = 5 into the expression:
√(5^2 - 2(5) - 23)
√(25 - 10 - 23)
√(25 - 10 - 23)
√(-8)
This expression involves the square root of a negative number, which is undefined in the real number system. Therefore, the limit does not exist.

B. lim x-> -2
(4x^2 - 7x) / (6x + 10)

To find the limit, substitute x = -2 into the expression:
(4(-2)^2 - 7(-2)) / (6(-2) + 10)
(4(4) + 14) / (-12 + 10)
(16 + 14) / (-2)
30 / -2
-15

Therefore, the limit as x approaches -2 of the given expression is -15.

Note: The last part of your question contains unrelated information about a website and unrelated problems. If you have any additional questions or need further explanation, feel free to ask!