Question

Solve: a) $a)x^2+6x=0$ b) $(x–4)(5x+2)=0$ c) $x^2+3x–18=0$

Answer 1

a) $x^2+6x=0$

Step 1:- x(x + 6) = 0

Step 2:- x = 0 or x + 6 = 0

Step 3:- x = 0 or x = – 6

b) (x – 4) (5x + 2) = 0

Step 1:- x – 4 = 0 or 5x + 2 = 0

Step 2:- x = 4 or x = – $\frac{2}{5}$

c) $x^2+3x–18=0$

Step 1:- $x^2+6x–3x–18=0$

Step 2:- x(x + 6) – 3(x + 6) = 0

Step 3:- (x + 6) (x – 3) = 0 $\Rightarrow$ x + 6 = 0 or x – 3 = 0

Step 4:- x = – 6 or x = 3

Roots of the given equation are : – 6 and 3.