Tolong di bantu ya soal mtk nya. thanks yg no. 23 & 24.​

Jawaban:

5*2= 3*2+4*2 – 2*3*4 cos C

25 = 9+16-24cos C

25 = 25 – 24 cos C

25 – 25 = – 24 cosC

0 = – 24 cos C

Cos C = 0

C = 90°