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 ( 97+ )
Otras preguntas
A Prize wheel has the numbers 0 through 36 on equally spaced sectors. The wheel is spun and contestants win a prize if the wheel stops at the number they choose
What was the total production of gasoline and kerosene combined?
what is 5879 rounded to the nearest hundredth
Kingdom animalia includes a major phylum known as chordata, which includes the sub-phylum vertebrata. This includes lions like the ones shown above. The remain
An experimenter is randomly sampling 3 objects in order from among 48 objects. what is the total number of samples in the sample space?
how many types of nucleotides are present in DNA
Of five letters (a, b, c, d, and e), two letters are to be selected at random without replacement. how many possible selections are there
Help please Match each point with one of the following rational number: A=-5/16,B=-9/16,C=-0.7,D=-0.4 A=-0.4,B=-0.7,C=-5/16,D=9/16 A=9/16,B=-5/16,C=-0.4,D=-0.7
The density of light oil is 0.78 kg/L. What is the volume of 5.72 kg of this oil in units of cm3?
Two integers are 38. find the two integers if the larger is 2 less than three times the smaller
