Question

Estimate the intercepts of the graph of the function.

-4
4
-4
y
8 x
y=x²-3x - 4
O x-intercepts: about -1 and -4, y-intercept: about -4
O x-intercepts: about -4 and 4, y-intercept: about -4
O x-intercepts: about -1 and 4, y-intercept: about -4
O x-intercepts: about -1, y-intercept: about -4

Answer 1

Answer: x-int=-1 and x-int=4 and y-int=-4 ==> 3rd option

Explanation:

x-int: 0=x^2 - 3x - 4 ==> x-int is at x-axis where y=0

0=x^2 - 4x + x - 4

0=x(x-4) + 1(x - 4)

0=(x+1)(x-4)

x+1=0 ==> x=-1

x-4=0 ==> x=4

x-int: y=0^2 - 3(0) - 4 ==> y-int is at y-axis where x=0

y=0-0-4

y=-4

x-int=-1 and x-int=4 and y-int=-4 ==> 3rd option