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
To get the vertex of the parabola we proceed as follows;
y=-7(x-4)^2-5
The above can be written as:
y=-7x^2+56x-117
The values of a,b and c are:
a=-7, b=56 and c=-117
x=-b/(2a)
x=-56/(-7*2)=4
but;
y=-7x^2+56x-117
y=-7(4)^2+56(4)-117
y=-5
Thus;
x=4 and y=-5
The vertex will be at point (4,-5)
Answer:
Neither
Explanation:
The slope-intercept form of the equation of a line is generally given as;

where m = the slope of the line
b = the y-intercept of the line
Two lines are said to be parallel if they have the same slope. Looking at the two given equations below, we see that the slope of the 1st one, 5/7, is different from the slope of the 2nd one, 7/5;

Two lines are said to be perpendicular if their slopes are negative reciprocals of each other, let's go ahead and compare their slopes;

So the two lines are not perpendicular to each other. It, therefore, means that the correct answer will be Neither.
Answer:
The substance decays by 7.5% every year
Step-by-step explanation: