Answer:
A) 2a + 6
Step-by-step explanation:
(5a + 3) + (2a + 3) + x = 9a + 12
Add both side lengths plus the unknown side to equal the perimeter.
7a + 6 + x = 9a + 12
-7a -6 -7a -6 Subtract 7a + 6 on both sides
x = 2a + 6 This is the missing side length.
Answer:
y² + 10y + 6x + 58 = 0
Step-by-step explanation:
Focus of the parabola has been given as (-7, -5) and directrix as x = -4
Let a point on the parabola is (x, y).
By the definition of a parabola, "distance of a point on parabola is equidistant from focus and directrix".
Distance from focus of the given point = 
Distance of the point from directrix = 
Therefore, equation of the parabola will be,


x² + 14x + 49 + y² + 10y + 25 = x² + 8x + 16
y² + 14x + 10y + 74 = 8x + 16
y² + 10y + 6x + 58 = 0
Slope = -1 -4 / 4 --1
slope = -5 / 5
slope = -1
the answer is already given, plz explain