yoakfordoVenia yoakfordoVenia
  • 25-11-2016
  • Mathematics
contestada

where does the graph of y=2x2-x-3 cross as the x-axis?

Respuesta :

MissPhiladelphia
MissPhiladelphia MissPhiladelphia
  • 25-11-2016
This can be determined by finding the x-intercept. In doing so, we let y=0 to find the value of x.

y= 2x^2 -x -3
[0 = 2x^2 -x-3]÷2
0 = x^2 -1/2 x - 3/2

Complete the squares:

1/16 + 3/2 = x^2 - 1/2x + 1/16
25/16 = (x -1/4)^2
sqrt (25/16) = x - 1/4
+/- 5/4 = x - 1/4

Thus,
x = 1/4 + 5/4 = 3/2
x = 1/4 - 5/4 = -1

Thus, the graph crosses at x = 3/2 and x = -1.
Answer Link

Otras preguntas

The Missouri compromise was written to address what problem?
what about thoreaus night in jail made him angry
Why is age an important determinant in decisions regarding migration?
All simple machines are variations of two basic machines. True False ...?
classify each triangle write acute,right or obtuse
208/600 as a decimal
write four numbers that round to 700000 when rounded to the nearest hundred thousand
Why does saponification produce sodium lactate (and not lactic acid) as the final product??
A(r) is a function that gives the area of a circle with radius r. It can be written in equation form as A(r) = 3.14r2. What is the value of A(3)? A(r) is a func
Which of these was a DIRECT result of the failed slave revolt of Nat Turner in 1831? A) Southern legislatures reexamined the moral foundation of keeping milli