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 ( 58+ )
Otras preguntas
This 1970s photograph records. A. a single isolated event in the United States related to gas production B. an explanation for détente, or the cooling period wi
separating a solid from a liquid by evaporating is called _____ a) filtration b) condensation c) solution d) distillation
Tell me ways to remember answers ?
which is parallel to y = 3x − 5?
submits to the will of Allah is known as what
How do plants play an important role in preventing wind erosion
Describe how the lac operon functions, and explain how it permits E. coli to produce the enzymes needed to break down lactose when it is present in the bacteriu
Some investments in the stock market have earned 10% annually. At this rate , earnings can be found using the formua A=P(1.10)^n, where A is the total value of
Paleontologists study the remains of organisms that lived in the past. Many of these remains are preserved in rocks. Which two parts of the earth system is a pa
how do you simplify algebraic expressions ?