Answer:
X=50
Step-by-step explanation:
x is the angle
180 - x is its suplement
90 - x is its complement
(180 - x) - 3(90 -x) = 10
180 - x -270 +3x = 10
-90 + 2x = 10
2x = 100
X = 50
Whenever you face the problem that deals with maxima or minima you should keep in mind that minima/maxima of a function is always a point where it's derivative is equal to zero.
To solve your problem we first need to find an equation of net benefits. Net benefits are expressed as a difference between total benefits and total cost. We can denote this function with B(y).
B(y)=b-c
B(y)=100y-18y²
Now that we have a net benefits function we need find it's derivate with respect to y.

Now we must find at which point this function is equal to zero.
0=100-36y
36y=100
y=2.8
Now that we know at which point our function reaches maxima we just plug that number back into our equation for net benefits and we get our answer.
B(2.8)=100(2.8)-18(2.8)²=138.88≈139.
One thing that always helps is to have your function graphed. It will give you a good insight into how your function behaves and allow you to identify minima/maxima points.
56% interest will be earned
Answer:
(c) -3.8, 3
Step-by-step explanation:
The solutions to the equation f(x) = g(x) are the values of x where the function values are equal. These are the x-coordinates of the points where the graphs of y=f(x) and y=g(x) intersect each other.
<h3>Points of intersection</h3>
The points where the graphs cross can be estimated to be ...
(-3.8, 6.5) and (3, -6)
The x-coordinates of these points are the solutions to the equation:
x = -3.8, 3
AD || BC and BD is the transversal,
Therefore, angle DBC = angle ADB = 42° [alternate angles]
AD || BC and BD is the transversal,
angle BAD + angle ABD + angle DBC = 180° [co-interior angles]
or, 106°+ angle ABD + 42° = 180°
or, 148° + angle ABD = 180°
or, angle ABD = 180°-148° = 32°
Therefore, angle ABC = (32+42)° = 74°
AB||CD and BC is the transversal,
angle ABC + angle BCD = 180° [co-interior angles]
or, 72+2x+12 = 180
or, 84+2x = 180
or, 2x=180-84 = 96
or, x = 48
Answers: a)48°
b)42°
c)72°