Answer:
I think the answer is C sorry if I'm wrong but hope I helped
(ab+3)(ab−3)
=(ab+3)(ab+−3)
=(ab)(ab)+(ab)(−3)+(3)(ab)+(3)(−3)
=a^2b^2−3ab+3ab−9
=a^2b^2−9
19) B
20) D
21) A
22) B
23) C
24) C
Answer:
Teacher is 27 years old
Step-by-step explanation:
(1/2)(t - 3) = (1/3)(t + 9)
multiply by 6 to clear the fraction
3(t - 3) = 2(t + 9)
Distribute
3t - 9 = 2t + 18
Subtract 2t from both sides
t - 9 = 18
Add 9 to both sides
t = 27
Teacher is 27 years old
M=-1/2 because you do y1-y2 over x1-x2 and end up with 2/-4 but simplified is -1/2