90 is the LCM of 30 and 45
(6y - 11)(6y + 11) = ay
² - b |use (a - b)(a + b) = a² - b²
(6y)² - 11² =ay² - b
36y² - 121 = ay² - b |add b to both sides
ay² = 36y² - 121 + b |divide both sides by y² ≠ 0
a = (36y² - 121 + b)/y²
Answer:
Step-by-step explanation:
2{5x²-15+(-9xy²)}-(2y²+4x-xy²)+3x²
=2{5x²-15-9xy²}-(2y²+4x-xy²)+3x²
=10x²-30-18xy²-2y²-4x+xy²+3x²
=13x²-2y²-17xy²-4x-30