Tolong jawabin yg no. 3 dan 4….Yg udh jwb makasih

3. 12x=180

x=15

B1=A1=5×15=75

4. n+2n+18=180

3n=162

N=54

M=2×54+18=126

M-N=126-54=72

No 3

Sudut A1 sehadap dengan sudut B1.

Maka sudut A1 = B1

A1 : B2 = B1 : B2 = 7:5

B1 + B2 = 180° krn berpelurus

B1 = 7/(7+5) × 180°

= 7/ 12 × 180°

= 7 × 15°

= 105°

No 4

M – 2N = 18°—> M = 2N + 18°

M dan N dalam sepihak

= M + N = 180°

M+ N = 180°

2N + 18° + N = 180°

3N = 180° – 18°

3N = 162°

N = 162° ÷ 3 = 54°

M = 2N + 18°

= (2×54°) + 18°

= 108° + 18° = 126°

M -N = 126° – 54° = 72°