Answer:
A. 17
Step-by-step explanation:
using the cosine rule (also see attached for reference):
AB² = BC² + AC² - 2·AC·BC cos C
2·AC·BC cos C = BC² + AC² - AB²
Given that AC = 18, AB = 12 and BC = 18, substituting these into the formula
2(18)(28) cos C = 28² + 18² - 12²
1008 cos C = 964
cos C = 964/1008
cos C = 0.9563
C = cos⁻¹ 0.9563
C = 16.99 ( = 17° rounded to nearest degree)
Step-by-step explanation:
5x^2+2x=1
5x^2+2x-1=0
x=-b+/-√b^2-4ac÷2a
x=-2+/-√-2^2-(4×5×-1)÷2×5
x=-2+/+√4--20÷10
x=-2+/-√24÷10
x=-2+√24÷10 or -2-√24÷10
x=-2+4.9÷10 or -2-4.9÷10
x=2.9÷10 or -6.9÷10
x=0.29 or -0.69
1 times 729=729 so
1mile=1.61kiloneter
multiply both sides by 729 to get 729 miles on left side
729 miles=1173.69 kilometer
whole
1173.6
6>5 so round up
1174
answer is 1174 kilometer
4+3p≥40
He needs to have 40 or more to get to the finals so 4+3p has to be 40 or more