Please, use " ^ " to denote exponentiation: p(t) = t^2 + 5t + 6.
To find the critical points, differentiate p(t) with respect to t, set the result = to 0, and then solve the resulting equation for t:
p '(t) = 2t + 5 = 0
Solving for t: 2t = -5, and so t = -5/2. (-5/2, p(-5/2)) is the critical point. That evaluates to (-5/2, -0.25). This happens to be the vertex of a parabola that opens up.
Answer:
A, C, D
Step-by-step explanation:
Consider triangles NKL and NML. These triangles are right triangles, because

In these right triangles:
- reflexive property;
- given
Thus, triangles NKL and NML by HA postulate. Congruent triangles have congruent corresponding parts, so
![\overline{KN}\cong \overline{NM}\\ \\\overline{KL}\cong \overline{LM}\ [\text{option D is true}]](https://tex.z-dn.net/?f=%5Coverline%7BKN%7D%5Ccong%20%5Coverline%7BNM%7D%5C%5C%20%5C%5C%5Coverline%7BKL%7D%5Ccong%20%5Coverline%7BLM%7D%5C%20%5B%5Ctext%7Boption%20D%20is%20true%7D%5D)
Since

then
![7x-4=5x+12\\ \\7x-5x=12+4\\ \\2x=16\\ \\x=8\ [\text{option A is true}]\\ \\MN=KN=7\cdot 8-4=56-4=52\ [\text{option C is true}]](https://tex.z-dn.net/?f=7x-4%3D5x%2B12%5C%5C%20%5C%5C7x-5x%3D12%2B4%5C%5C%20%5C%5C2x%3D16%5C%5C%20%5C%5Cx%3D8%5C%20%5B%5Ctext%7Boption%20A%20is%20true%7D%5D%5C%5C%20%5C%5CMN%3DKN%3D7%5Ccdot%208-4%3D56-4%3D52%5C%20%5B%5Ctext%7Boption%20C%20is%20true%7D%5D)
Option B is false, because KN=52 units.
Option E is false, because LN is congruent KN, not LM
C is the correct answer. An equilateral triangle is a type of triangle.
The ratio of the shortest sides is 12/5. Multiplying the other two sides of the smaller triangle by that ratio gives 15 and 18, so the ratios of all sides are the same. The triangles are similar.
ABC ~ ZYX
The largest/smallest scale factor is 12/5 = 2.4.