Question 1075927
Let n be the first even number. Then the next two even numbers are n+2 and n+4. So:
n²+(n+2)²-84=(n+4)²
n²+n²+4n+4-84=n²+8n+16
n²-4n-96=0
(n+8)(n-12)=0
n=-8 or 12
We get a positive value for n of 12; then n+2 and n+4 are 14 and 16, respectively. ☺☺☺☺