Answer:
Step-by-step explanation:
The roots of a function are the x-intercepts. By definition, the y-coordinate of points lying on the x-axis is zero. Therefore, to find the roots of a quadratic function, we set f (x) = 0, and solve the equation, ax2 + bx + c = 0.
Answer:
1) 128°
2) 126°
3) 108°
<h2>
Question one:</h2>
The square in the corner means 90°. If you add the interior angles of any triangle together, you get 180. in this case, x is in exterior angle, so you subtract it from 180 to get the interior angle.
38 + 90 + (180-x) = 180
38 + 90 + 180 - x = 180
38 + 90 + 180 - 180 - x = 0
38 + 90 + 180 - 180 = x
128 = x
<h2>
Question two:</h2><h2>
</h2>
again, adding all the interior angles makes 180°. use this to make the equation.
3x + (5x-6) + 90 = 180
3x + 5x - 6 = 90
8x = 96
x = 12.
x isn't the answer the question wants, however. if you look at the drawing, the angle that's supplementary to 5x-6 is the exterior angle. so,
180 - (5x-6) = the answer
180 - 5x + 6 = the answer
substitute x for 12
180 - 60 + 6 = the answer
126 = x
<h2>Question three</h2>
again, adding all the interior angles together makes 180°.
(a + 10) + 44 + (180-2a) = 180
a + 10 + 44 + 180 - 2a = 180
-a + 234 = 180
234 - 180 = a
54 = a
however, the question is looking for the exterior angle, not a. in this case, the exterior angle is 2a, so just multiply 54 by 2.
x = 108
Answer:
the dimensions of the box that minimizes the cost are 5 in x 40 in x 40 in
Step-by-step explanation:
since the box has a volume V
V= x*y*z = b=8000 in³
since y=z (square face)
V= x*y² = b=8000 in³
and the cost function is
cost = cost of the square faces * area of square faces + cost of top and bottom * top and bottom areas + cost of the rectangular sides * area of the rectangular sides
C = a* 2*y² + a* 2*x*y + 15*a* 2*x*y = 2*a* y² + 32*a*x*y
to find the optimum we can use Lagrange multipliers , then we have 3 simultaneous equations:
x*y*z = b
Cx - λ*Vx = 0 → 32*a*y - λ*y² = 0 → y*( 32*a-λ*y) = 0 → y=32*a/λ
Cy - λ*Vy = 0 → (4*a*y + 32*a*x) - λ*2*x*y = 0
4*a*32/λ + 32*a*x - λ*2*x*32*a/λ = 0
128*a² /λ + 32*a*x - 64*a*x = 0
32*a*x = 128*a² /λ
x = 4*a/λ
x*y² = b
4*a/λ * (32*a/λ)² = b
(a/λ)³ *4096 = 8000 m³
(a/λ) = ∛ ( 8000 m³/4096 ) = 5/4 in
then
x = 4*a/λ = 4*5/4 in = 5 in
y=32*a/λ = 32*5/4 in = 40 in
then the box has dimensions 5 in x 40 in x 40 in
