Question

What two numbers add up to 55 and multiply to -375​

Answer 1

Answer:

-6.13406 and 61.13406

Step-by-step explanation:

x + y = 55

x × y = -375

y = 55 - x

x × (55 - x) = -375

55x -x² = -375

x² - 55x - 375 = 0

solution of a quadratic equation :

x = (-b ± sqrt(b² - 4ac))/(2a)

a=1

b=-55

c=-375

x = (55 ± sqrt(55² + 4×375))/2 = (55 ± sqrt(4525))/2 =

= (55 ± sqrt(25 × 181))/2 = (5×11 ± 5×sqrt(181))/2 =

= 5/2 × (11 ± sqrt(181)) =

= 61.13406... or -6.13406...

y = 55 - 5/2×(11 ± sqrt(181)) = 55/2 ± 5/2×sqrt(181) =

= -6.13406... or 61.13406...