Question

guys plz do answer me for the 5th question.... irrelevant answers will be reported on the spot....​

Answer 1

Step-by-step explanation:

We have,

${x}^{2} - 11x - 80 = 0$

$= {x}^{2} - 16x + 5x - 80$

$= x(x - 16) + 5(x - 16)$

$= (x - 16)(x + 5)$

Answer 2

Method 1 ⇒ Factorization

Let's solve your equation step-by-step

$x^{2} - 11x - 80 = 0$

Step 1: Factor left side of equation.

⇒ $(x+5)(x-16)=0$

Step 2: Set factors equal to 0.

⇒ $x+5=0 \ or \ x-16=0$

⇒ $x=-5 \ or \ x=16$

$\rule{300}{1}$

Method 2 ⇒ Using Quadratic Equation

Let's solve your equation step-by-step

$x^{2} - 11x - 80 = 0$

For this equation: a = 1, b = -11, c = -80

⇒ $1x^{2}+-11x+-80=0$

Step 1: Use quadratic formula with a = 1, b = -11, c = -80.

⇒ $x=\dfrac{-b\±\sqrt{b^{2}-4ac} }{2a}$

⇒ $x=\dfrac{-(-11)\±\sqrt{(-11)^{2}-4(1)(-80)} }{2(1)}$

⇒ $x=\dfrac{11\±\sqrt{121-4(-80)} }{2}$

⇒ $x=\dfrac{11\±\sqrt{121+320} }{2}$

⇒ $x=\dfrac{11\±\sqrt{441} }{2}$

⇒ $x=16 \ or \ x=-5$

$\rule{300}{1}$

$\bf \therefore x=16 \ or \ x=-5 \ in \ the \ equation =>\ x^{2} - 11x - 80 = 0$