Answer:
a. x² + 10x + 25
Step-by-step explanation:
because
(x + 5)² = (x + 5)(x + 5) = x² + 5x + 5x + 25 = x² + 10x + 25
so, it is a perfect square of (x + 5).
Answer:
x = 10
Step-by-step explanation:
Use Pythagorean theorem to find the value of x
Focus only on one half of the triangle
if we slice the triangle in half, we get a right angle triangle
the base will now be 12/2 = 6
Pythagorean theorem says that 
plug 6 as a and 8 as b.
this should give you 100
now take the square root to find c (which equals x)
Ta-da!
Answer:
y=4x+47
I wanted to wait for the person who originally said the answer but it's been a while and I kinda want the points. Sorry