Why might the triangulation method not always produce an exact point (other than any measurement errors)

What is the factored form of x2 − 4x − 5? (x + 5)(x − 1) (x + 5)(x + 1) (x − 5)(x − 1) (x − 5)(x + 1)

Jamie went to home depot. she bought 25 bags of soil that cost $9 per bag. she bought 15 pots at $8 each, and she bought 23 bags of pebbles at $15 each. she used a coupon that gave her $5 off for every 100 dollars she spent. how much did jame pay at the end?

45% of the trees in a park are apple trees. there are 27 apple trees in the park. how many trees are in the park in all?