There are 45 girls in Jonathan's class.
Answer:

Step-by-step explanation:

D (0, -3)
E (1, 0)
F (2, -1)
16. M = 1/5
17. M =3
18. Slope 1/4 and y-intercept (0,2)
Step-by-step explanation:
4x2 - 25b2
We can solve it by the squares so
(2x - 5b) (2x + 5b)
2) x2 - 81
The same case is here so
(x - 9) (x + 9)