Question

P2 – 14p – 72 = 0

p2 – 14p = 72

p2 – 14p + 49 = 72 + 49





Which describes the solutions of the equation?

Answer 1

Since 7 and 11 are both rational, the sum and difference are rational

(p−7)=±11

Answer 2

p =18, -4

Explanation:

Solve the equation using middle term spiting:

`p^2 - 14p + 49 = 72 + 49`

`p^2 - 14p +49-49 = 72`

`p^2 - 14p  = 72`

`p^2 - 14p-72=0`

`p^2 - 18p+4p-72=0`

`p(p-18)+4(p-18)=0`

`(p-18)(p+4)=0`

`p-18=0 , p+4 =0`

`p=18 , p = -4`

Thus the solution of the equation is p =18, -4