Question

Solve the following equation (Find x)
a) (5x+2)(5x-2)+(5x-2)(x-1)-(5x-2)²​

Answer 1

Applying the formulae, (a+b)2+(a−b)2=2(a2+b2)

and (a+b)2−(a−b)2=4ab where a=5x;b=2

4×(5x)×22((5x)2+22)=1213

20x25x2+4=1213

On cross multiplying and simplifying,

75x2−65x+12=0

75x2−20x−45x+12=0

5x(15x−4)−3(15x−4)=0

(5x−3)(15x−4)=

x={53,154}={0.6,0.27}

Hence, m=0.6

you please do like this method

Answer 2

`~~~~~~(5x+2)(5x-2)+(5x-2)(x-1)-(5x-2)^2 = 0\\\\\implies (5x-2)(5x+2+x-1-5x+2)=0\\\\\implies (5x-2)(x+3)=0\\\\\implies x+3 = 0~~ \text{or}~~ 5x -2 = 0\\\\\implies x = -3,~ x =\frac 25`