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

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

which word below completes this synonym/antonym analogy? failure: success:: forget: A. remember B. ignore C. disregard D. neglect

1.) (-4,-3); m=2/3 given point, then graph a line with the given slope

Consider the graph below Find the y-intercept and slope of the line. Fill in the blanks in the statement. The y-intercept of the line is ______, and the slope o

2. The grocery store charges $10.35 for 5 bags of oranges. If someone bought 9 bags of oranges, how much would it cost them?

Actual distance = _ miles

2. The grocery store charges $10.35 for 5 bags of oranges. If someone bought 9 bags of oranges, how much would it cost them?

Aria is taking an anatomy class and is trying to remember the names of the bones of the skull, specifically the cranial bones. She decides to remember the six b

There are 36 students in Mr. Meyer's class. Of those students, 5/12 played tag at recess, 1/3 played kickball, and the rest played basketball. How many students

one should not boast for his success ( one’s success)

7 – 2 • 5 + 9 • 3 Question 1 options: 24 –30 102 18