Question

simplify this number (4-√5)²​

Answer 1

(4√5)²

= 16 x 5 ( Squaring on both the sides)

= 80

I hope it's help for u ☺️

Answer 2

$\huge\mathfrak\red{question}$

simplify this number (4-√5)²

$\huge\mathfrak\blue{Solution}$

By applying the formula

$\boxed{\pink{(a-b)²= a² - 2ab + b²)}}$

(4-√5)² = 4² - (2.4.√5)+ ✓5²

= 16 - 8√5 + 5

= 21 - 8√5