Answer:
x = 4
-4x+21 => 5
Step-by-step explanation:
The given triangle in the picture is isosceles triangle which means that two sides of the triangle are equal.
So,
[tex]Side\ 1: -4x+21\\Side\ 2: -4x+21\\Side\ 3: 6\\Perimeter = 16[/tex]
Now
Putting all the values in equation for perimeter
[tex]Side\ 1+Side\ 2+Side\ 3 = 16\\-4x+21 -4x+21 + 6 =16\\-8x +48 = 16\\-8x = 16-48\\-8x = -32\\\frac{-8x}{-8} = \frac{-32}{-8}\\x = 4[/tex]
Putting x = 4 in side 1
[tex]=-4(4)+21\\= -16+21\\=5[/tex]
Hence,
x = 4
-4x+21 => 5
