Question #7922f

2 Answers
Nov 29, 2017

Yes

Explanation:

Using Pythagorus

For a right angled triangle h^2 = a^2 + b^2 where h is the hypotenuse and a and b are the other two sides

conversely if the sum of the squares of a and b = the square of the hypotenuse, then the triangle must be right-angled.

Substitute in what we know
15^2 = 9^2 + 12^2

Simplify
225 = 81 + 144 = 225

Therefore the triangle is a right-angled triangle

Nov 29, 2017

"right triangle"

Explanation:

"using the "color(blue)"converse theorem of Pythagoras"

"if the longest side squared is equal to the sum of the "
"other two sides squared then it is a right triangle"

rArr15^5=225larrcolor(blue)"longest side squared"

9^2+12^2=81+144=225

"since "15^2=9^2+12^2

"then it is a right triangle"