Question

Solve. x² + 20x + 100 = 50
A)x=−10±52√
​B)x=50±252√ ​
​C) x=10±52√ ​ ​
​D)x=50±52√ ​

Answer 1

x² + 20x + 100 = 50

x = −10 ± 5√2

Answer 2

Solve. x²+ 20x + 100 = 50

Subtracting 50 from both sides

$x^{2} +20x+100-50=50-50$

$x^{2} +20x+50=0$

To solve the quadratic equation, let us use quadratic formula

For, $ax^{2} +bx+c=0$ , $x=\frac{-b+-\sqrt{b^{2}-4ac}}{2a}$

So, a=1, b=20, c=50

So, we get,

x=$\frac{-20+-\sqrt{20^{2}-4*1*50}}{2*1}$

$x=\frac{-20+-\sqrt{400-200}}{2}$

$x=\frac{-20+-\sqrt{200}}{2}$

$x=\frac{-20+-10\sqrt{2}}{2}$

$x=\frac{-10+-5\sqrt{2}}{1}$

$x=-10+-5\sqrt{2}$

Option(a) Answer

So, x=-10+5$\sqrt{2}$

or, x=-10-5$\sqrt{2}$