What is the vertex of y= (x − 3)(4x + 2) y=(x3)(4x+2)?

1 Answer
Jun 17, 2018

Vertex is at (1.25 , -12.25)(1.25,12.25)

Explanation:

y=(x-3)(4 x+2) or y= 4 x^2 -10 x -6y=(x3)(4x+2)ory=4x210x6

a= 4 , b= -10 ,c =-6 ; [y= ax^2+bx+ca=4,b=10,c=6;[y=ax2+bx+c

Vertex ( x coordinate) is v_x= (-b)/(2 a)=10/8=1.25 vx=b2a=108=1.25

Putting x=1.25x=1.25 in the equation we get v_yvy

Vertex ( y coordinate) is

v_y= 4 *1.25^2-10 *1.25-6=-12.25vy=41.252101.256=12.25

Vertex is at (1.25, -12.25)(1.25,12.25)

graph{y=(x-3)(4x+2) [-40, 40, -20, 20]} [Ans]