Answer:
see in the picture, the perimeter of this rectangle is
2( x + 3x) = 8x but the perimeter is 65.6
=> 8x = 65.6
<=> x = 65.6/8
=> x = 8.2
Answer:
15×2x
Step-by-step explanation:
Let's first rewrite it in vertex form.
Start by completing the square.
y = x² + 4x + 4 - 4 - 1
y = (x + 2)² - 5
(x + 2)² = y + 5
Now, 4a = 1; a =

So, the vertex form is (x + 2)² = 4(

)(y + 5)
So, we know that the vertex is at (-2, -5).
Since it's a concave up parabola, we just have to change the y-value to find the focus.
∴ F(-2, -5 +

)
F(-2,

)
Y = (-2x +2)^2 +8
(-2x^2 +4) +8
-2x^2 +12