Answer:
34,220
Step-by-step explanation:
Because order doesn't matter, but the numbers can't be repeated, we need to find the number of combinations where 3 individual numbers can be chosen out of 60 possible numbers using the binomial coefficient:

Thus, Elias can make 34,220 unique 3-number codes given 60 different numbers.
X=32
ABC=264
Look at image for explanation
Slope is rise/run or y2-y1/x2-x1. So to find the slope, find two points where the point is exact, then do the equation. That's the best I can explain, sorry if this doesn't help at all.
Answer:
Be careful what you wish for.
Step-by-step explanation: