tolong jawab soal no 15,16,17 dan 18 beserta cara nya yaa,, tolong yaa,,

15) 3√18 - 8√2 - √50
= 3√9.2 - 8√2 - √25.2
= 9√2 - 8√2 - 5√2
= -4√2
• Jawaban: C

16) √18 x √12 : √3
= √18 x √4
= √9.2 x 2
= 3√2 x 2
= 6√2
• Jawaban: B

17) (2^-2 x 3⁴) / (6³)
= (2^-2 x 3⁴) / (2³ x 3³)
= 2^-5 x 3
= 3 / 2^5
= 3 / 32
• Jawaban: D

18) 8 / (3+√5)
= 8(3-√5) / (3+√5)(3-√5)
= 8(3-√5) / 9-5
= 8(3-√5) / 4
= 2(3-√5)
= 6 - 2√5
• Jawaban: C