Question

How do you solve `x^2 - x - 12 = 0` graphically?

Answer 1

`x=-3" or "x=4`

Explanation:

`"given the graph of "x^2-x-12`

`"the solutions are the values of x where the graph crosses"`
`"the x-axis"`
graph{(y-x^2+x+12)((x+3)^2+(y-0)^2-0.04)((x-4)^2+(y-0)^2-0.04)=0 [-10, 10, -5, 5]}

`rArrx=-3" or "x=4" are the solutions"`

`"we can verify this algebraically by solving"`

`x^2-x-12=0`

`rArr(x-4)(x+3)=0`

`x-4=0rArrx=4`

`x+3=0rArrx=-3`