jahajahaja jahajahaja
  • 01-09-2016
  • Mathematics
contestada

What are the zeros of f(x)=x^2+x-20?
A.x=-2 and x=10
B.x=-10 and x=2
C.x=-5 and x=4
D.x=-4 and x=5

Respuesta :

dalendrk
dalendrk dalendrk
  • 02-09-2016
f(x) = x² + x - 20 = x² + 5x - 4x - 20 = x(x + 5) - 4(x + 5) = (x + 5)(x - 4)

f(x) = 0 ⇔ (x + 5)(x - 4) = 0 ⇔ x + 5 = 0 or x - 4 = 0 ⇒ x = -5 or x = 4

Answer: C. x = -5 and x = 4.
Answer Link

Otras preguntas

9% of 750............................
Who studied anatomy to improve his paintings? A. Leonardo da Vinci B. Michaelangelo C. Baldassare Castiglione D. Isabella d'Este E. Medici G. Titian
What is the value of the expression k – 14 when k = –17? A. –31 B. –3 C. 3 D. 31
What is the tens fact for 14-6
R and s configuration
Does Landon ohse like me
Answer questions 1 through 15
Who was Moses? A. the Hebrew leader who introduced the Ten Commandments B. the Egyptian head of the polytheistic church C. the Hebrew son who sold his broth
five most significant reforms of octavian
If you have 598gallons of fuel and a car that does 10miles to the gallon how many miles can you drive?