Answer:
15a² + 21a + 19 = 0
Step-by-step explanation:
Given
(4a + 3)² = (a + 5)(a - 2)
(4a + 3)(4a + 3) = (a + 5)(a - 2 ) ← expand both sides using FOIL
16a² + 24a + 9 = a² + 3a - 10 ( subtract a² + 3a - 10 from both sides )
16a² - a² + 24a - 3a + 9 + 10 = 0 ← collect like terms
15a² + 21a + 19 = 0
