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

Otras preguntas

Conjugate the verb in parenthesis according to the subject. él ________ (tener)

What sort of textual evidence should you put in your introductory paragraph? A. a dictionary definition B. a quote from a contemporary reference O C. a piece of

i need help 5times 10 +25-9+2times2

4 A, B & C lie on a straight line. D, C & E lie on a different straight line. Angle y = 101° and angle z = 52°. Work out x , explaining each stage

If f(x) = -7x + 2 and g(x) = x+3, what is (fºg)(-2)? Enter the correct answer

Not a question, but just thought I'd say that Deku wet his sheets until he was like.. 8. He always cried cus he messed up another one of his All Might underwear

what main structure did Carrie use in paragraph 9, and why?

How have the Walls children's relationships with each other changed since the beginning of the book? hormonolity Sunnot your conclusions with specific

what is the chemical name for Se8O7

below is a base sequence for the normal protein for normal hemogoblin and the base sequence for the sickle cell hemogoblin. Transcribe and translate the normal