Explanation:
Given equation is 4x²-24x-36 = 0
⇛ 4(x²-6x-9) = 0
⇛ x²-6x-9 = 0
⇛ x²-2(x)(3) = 9
On adding 3² both sides then
⇛ x²-2(3)x)+3² = 9+9
⇛ (x-3)² = 18
⇛ (x-3) = ±√18
⇛ x-3 = ±√(2×9)
⇛ x-3 = ±3√2
⇛ x = 3±3√2
⇛ x = 3+3√2 or 3-3√2
