panda557
panda557
03-06-2016
Mathematics
contestada
What is x^2+x-20=0.
please help
Respuesta :
meerkat18
meerkat18
03-06-2016
x² + x - 20 = 0
x² = x * x
x = the sum of the factors of -20
-20 ⇒ 1 x 20
2 x 10
- 4 x 5 ⇒ only these factors can arrive to a sum of 1
(x - 4)(x + 5) = x(x+5) - 4(x+5) = x² + 5x - 4x - 20 = x² + x - 20
x - 4 = 0
x = 4
x + 5 = 0
x = -5
Answer Link
VER TODAS LAS RESPUESTAS ( 78+ )
Otras preguntas
Si n es un número impar,¿ cual de las siguientes opciones representa un numero par? a) 2n +1 b) n(n+2) c) n+(n-1) e) 2(n+1)
The price (P) of designer jeans is affected by the supply (S) and the demand (D). Which of these can cause an increase in the price of designer jeans?
How long does it take, in minutes, for a Russian Avangard Missile, which travels at a speed of Mach 27, to travel the distance from Moscow to Kabul, Afganistan,
How many republicans and democrats are in the senate now
Evaluate the numerical expression and match To its value
aaaaaaa help me with chemistry Bases: are generally proton acceptors produce OH− ions in solution are electron pair donors may include all of these characterist
What mathematical evidence can you provide to support the assertion that the universe is electrically neutral on large scales?Ryden, Barbara. Introduction to Co
2 sin 2theta = root 3 , find the value of theta
A car of mass 900 kg is traveling at 20 m/s when the brakes are applied. The car then comes to a complete stop in 5 s. What is the average power that the brakes
An article in the Sacramento Bee (March 8, 1984, p. A1) reported on a study finding that "men who drank 500 ounces or more of beer a month (about 16 ounces a da