(a) A, B,C, D are the four interior angles, taken in order, of a cyclic quadrilateral. Prove that: cot(A) + cot(B) + cot(C) + cot(D) = 0.

(b) If cos(x) + sin(x) = m and sec(x) + cosec(x) = n, prove that n(m^2- 1) = 2m.

Help will be greatly appreciated! Will award brainliest :)

answer: sorry i can't you.

step-by-step explanation:

step-by-step explanation:

the final amount you will pay is $68.04.

the tip is determined by the pre-tax amount, so we calculate the tip based on the original bill, not after we've added sales tax.

to find the tip:

we can divide 54.00 by 100 to get 1% of 54. then we multiply that by 18.

54 / 100 = .54

.54 x 18 = 9.72

tip = 9.72$

to find the tax:

we can divide 54.00 by 100 to get 1% of 54. then we can multiply that by 8 to get 8%.

54 / 100 = .54

.54 x 8 = 4.32

tax= 4.32

now we can add the tip and tax to the bill to get our total.

54 + 9.72 + 4.32 = 68.04

total: $68.04

step-by-step explanation: