Question

The sides of a triangle have lengths 2x + 2, 4x, and 5x + 1. The longest side of the triangle has a length of 5x + 1. For what values of x is the triangle obtuse?

Answer 1

Answer:

Step-by-step explanation:

(5x+1)²>(2x+2)²+(4x)²

25x²+10x+1>4x²+8x+4+16x²

5x²+2x-3>0

5x²+5x-3x-3>0

5x(x+1)-3(x+1)>0

(x+1)(5x-3)>0

x+1=0,gives x=-1

5x-3=0,gives x=3/5

x >0(because 4x should be >0)

side is always positive.

so x>3/5

again 5x+1<2x+2+4x

5x-6x<2-1

-x<1

x>-1

x=all real values >3/5