15. -6b+2-5b=36+6b
-11b+2=36+6b
-17b+2=36
-17b=34
b=-2
16. 48+32h=-39+3h
48+29h=-39
29h=-87
h=-3
17. -20r+5=-20r+20
5¥20
no solution
18. a+7=7a+21+18-6a
a+7=a+39
7¥39
no solution
19. -8b+24=24-24b
16b+24=24
16b=0
b=0
20. 5a+4=5a-10
4¥-10
no solution
Answer:
x^2+2x-8= x^2+10x-8x-80 =x(x+10)-8(x+10)
=( x-8) (x+10)
therefore x= 8 or x=-10
Dear sir, we know not what you mean.
A, and C
Hope this helped!
