Answer: 810
<u>Step-by-step explanation:</u>
There are 10 numbers to choose from. Since the 2nd digit and 3rd digit cannot repeat the number before it, they only have 9 numbers to choose from.
1st digit and 2nd digit and 3rd digit
10 choices x 9 choices x 9 choices = 810
Answer:
x²-7x=0
Step-by-step explanation:
please mark as brainliest
1.

so

Answers B and D.
2.

Answer D.
3.
The same as point 2. Answer D.
4.
Answer C.