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 ( 65+ )
Otras preguntas
importance of teeth in home science
Scientists have a theory about the shape of the Earth's surface that is accepted worldwide. A group of scientists have proposed a new theory about the shape of
Which statement is true?
When proofreading a message, the focus of the proofreading should be what?
I WILL VOTE MOST BRAINLY ANSWER. HELP ME PLEASE Part A: Factor x2a2 + 3xa2 + 2a2. Show your work. (4 points) Part B: Factor x2 + 2x + 1. Show your work. (3 poin
Wasn’t sure how to write this out : - )
If a pentagon is a regular pentagon, then what is the measure of each interior angle? A. 108° B. 36° C. 144° D. 72°
which of the following is true of the greenhouse effect? A. it helps regulate the temperature of earth B. it is only active during the day C. it has only existe
In a batch of 100 cell phones, there are, on average, 5 defective ones. if a random sample of 30 is selected, find the probability of having 2 defective phones.
the diagram above shows the countries's places on a spectrum based on their______a. economic systemsb. economic productionc. imports and exportsd. industrializa