Question

If m-n=16 and (m +n)(m+n) =400,then find mn.

Answer 1

Answer: (m-n) 2 = 16*16

m2 + n2 -2mn = 256

400 -2mn =256

-2mn = 256-400

-2mn = -144

mn = 72

Step-by-step explanation:

Answer 2

Answer:

36

Step-by-step explanation:

• m-n=16 and (m+n)(m+n)= 400
• m-n=16

1. m=16+n

• m²+n²= (m+n)(m+n)
• m²+n²=400
• m=√400-√n²

1. m=20-n

• 16+n=20-n
• n+n= 20-16
• 2n=4
• n= 2
• m=16+n
• m=16+2=18
• mn=18×2= 36