Question

(I) x²-8x = -16(ii) x²+2x+1 = 0(iii) 4x²-24x-36=0Solve please...........​

Answer 1

(I)

Given equation is x²-8x = -16

⇛ x²-8x+16 = 0

⇛ x²-4x-4x+16 = 0

⇛ x(x-4)-4(x-4) = 0

⇛ (x-4)(x-4) = 0

⇛ x-4 = 0 or x-4 = 0

⇛ x = 4 or x = 4

(ii)

Given equation is x²+2x+1 = 0

⇛ x²+x+x+1 = 0

⇛ x(x+1)+1(x+1) = 0

⇛ (x+1)(x+1) = 0

⇛ x+1 = 0 or x+1 = 0

⇛ x = -1 or x = -1

(iii)

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