Answer:
1) 6r+7=13+7r —> 7r–6r=7–13 —> r = – 6
2) 13–4x=1–x —> 4x–x=13–1 —> 3x=12 —> x=12/3 —> x=4
3)–7x–3x+2=–8x–8 —> –8x+7x+3x=2+8 —> 2x=10 –> x= 10/2 –> x= 5
4)–8–x=x–4x —> –x–x+4x=8 —> 2X=8 —> x= 8/2 —> x= 4
5) –14+6b+7-2b=1+5b —> 5b +2b –6b = –14+7–1 —> b=–8
6) n+2=–14–n —> n+n=–14–2 —> 2n = –16 —> n = – 16/ 2 —> n = – 8
7) n – 3n = 14 –4n —> n –3n + 4n = 14 —> 2n = 14 —> n = 14/ 2 —> n = 7
8) 7a – 3 = 3 + 6a —> 7a – 6a = 3 + 3 —> a = 6
9) 3(1–3x ) =2(–4x+7) —> 3 –9x = –8x+14 —> 9x–8x = 3–14 —> x = –11
10) –10 +x+4–5 =7x –5 —> 7x–x = –10+4–5 +5 —> 6x = –6 —> x= –6/6 —> x = –1
11) –8n +4(1+5n)=–6n–14 —> –8n +4 + 20n = – 6n– 14
20n –8n +6n= –14 –4 —> 18n = – 18 —> n = –18/18 —> n = –1
12) –6n–20=–2n +4(1–3n) —> –6n –20 = – 2n +4 –12n —> 12n +2n –6n = 4 +20 —> 8n =24 —> n = 24/8 —> n =3
I hope I helped you^_^
