РЕШЕНИЕ:
( a + 9b − _1) : __b__ =
a2−9ab___ a ___ 9b−a
( a + 9b − _1) : __b__ =
a(a-9b)___ a ___ 9b−a
a + 9b − (a-9b) : __b__ =
a(a-9b) __ __ ___ 9b−a
a + 9b − a + 9b : __b__ =
a(a-b) __ __ ___ 9b−a
18b __ : __b__ =
a(a-9b) __ 9b−a
18b __ ∙ a - 9b =
a(a-9b) __ -b
18 =
- a
18 __ = - 22.5
- 0.8
Ответ: - 22.5
