Question

If p+m=6 and p^3+m^3=72, then the value of pm is

Answer 1

Answer:

pm=8

Step-by-step explanation:

(p+m) = 6

cubing

(p+m)^3=(6)^3

p^3+m^3+3pm(p+m)=216

72+3pm(6)=216. (values given in the equation)

18pm=216-72

18pm=144

pm=144/18

pm=8

Answer 2

Answer:

p+m=6___(i)

3p+3m=72___(ii)

Let multiply the eq. one by 3.

-3p-3m=-18

3p+3m= 72

cancel out -3p by 3p

M=54

putting this value on eq. two

3p+3×54= 72

3p+162= 72

3p= 72-162

3p=- 90

p= -90/3

p= -30