That factors to (x + 5)(x + 4)
a2+9a+20 = (a+4)(a+5) when factored
7a = -12
a + 3a + 5a = 180 9a =180 a = 20
12a + 6b + 9a + 14b =(12a + 9a) + (6b + 14b) =21a + 20b
2a+5a+9a = 16a
(9a + 2)(9a + 2)
so 5a = -20 making a = -4
9a + 7b *remember to look and understand the letters!*
9a+21 3(3a+7)
The simplified expression is -9a -9b.
There is nothing you can do to 9a + 5 without knowing the value of a.
If that's 9a2, the answer is a(a2 - 9a + 3) x(5x2 + 3x - 1) -8d(d2 + 3d + 1)