Question

The sides of a triangle have lengths of x, x + 4, and 20. If the longest side is 20, which of the following values of x would make the triangle obtuse?

Answer 1

@khalilforthewin

Answer 2

what grade is this

Answer 3

10th Grade Geometry A

Answer 4

im a freshmen sorry

Answer 5

And I'm in 8th Grade, but thanks for the help. xD

Answer 6

im in 8th grade to but i take freshmen maath classes

Answer 7

When x^2 +(x+4)^2 =20^2 it is a right triangle
When x^2 +(x+4)^2 <20^2 it is an obtuse triangle
When x^2 (x+4)^2 >20^2 it is acute
x^2 +x^2 +8x +16 >400
2x^2 +8x -384>0
x^2 +4x-192>0
(x+16)(x-12) >0
when x<-16 the inequality is positive, but we ignore this answer since it is negative
When x>12 the triangle is acute.

Answer 8

Same, but sophomore math.

Answer 9

Yeah, already got the answer.

Answer 10

But thanks! (:

Answer 11

...

Answer 12

Sorry, lol.