Answer:
acute triangle
Explanation:
using the converse of the Pythagorean theorem.
if the square on the longest side is equal to the sum of the squares on the other two sides then the triangle is right.
let c be the longest side and a, b the two legs , then
• if a² + b² = c² , the triangle is right
• if a² + b² > c² , the triangle is acute
• if a² + b² < c² , the triangle is obtuse
here c = 9 , a = 6 , b = 7
c² = 9² = 81
a² + b² = 6² + 7² = 36 + 49 = 85
since a² + b² > c² , then the triangle is acute