Answer:
yes :
use the following formula :
a^2 +b^2 = c^2
now apply it to the problem :
5^2+12^2=13^2
do the exponent :
25 + 144 =169
now add
169 =169
if they are equal , then it is a right triangle .
rearrange the equation to where you set it equal to 0 by moving the 25 over.
n2 - 8n -9 = 0
now factor
(n-9)(n+1)
so n1 = 9
n2 = -1
The answer to the question is the first, third and fifth
Let's plug x= -1, y= 4 in the inequation, we have:
4< 2*(-1)+5
⇒ 4< -2+5
⇒ 4< 3 (false)
Therefore, (-1,4) is not a solution of the inequation y<2x+5~
