Answer:
1. 110°
2. 139°
Step-by-step explanation:
1. 180° in a triangle
180 - 40 - 30 = 110°
2. 180° in a triangle
angles on a straight line add up to 180°
180 - 64 - 75 = 41°
180 - 41 = 139°
Answer:
looking at the straight line, it touches the axis at (-2,0) and (6,0)
Step-by-step explanation:
Step-by-step explanation:
(a)
ii.
21 - 5 = 16 play only chess.
iii.
23 - 5 = 18 play only cards
5 play both.
that is 16+18+5 = 39 that play at least one of these games.
i.
so, 45 - 39 = 6 don't play any of these games.
(b)
we have 16+18 = 34 pupils out of 45 that play exactly one game.
so the probabilty to pick one of them is as usual
desired cases / total cases = 34/45 =
= 0.755555555... ≈ 0.76
You must develop a cost function C(x) and then minimize its value.
How much dwill the glass cost? It's $1 per sq ft, and the total area of the glass is 4(xh), where x is the length of one side of the base and h is the height of the tank. The area of the metal bottom is x^2, which we must multiply by $1.50 per sq ft.
This cost function will look like this: C(x) = 4($1/ft^2)xh + ($1.50/ft^2)x^2
but we know that (x^2)h= 6 cu ft, or h = (6 cu ft) / (x^2). Subst. this last result into the C(x) equation, immediately above:
C(x) = 4($1/ft^2)x[6 ft^3 / x^2] + ($1.50/ft^2)x^2
Let's focus on the numerical values and ditch the units of measurement for now:
C(x) = 4x(4/x^2) + 1.50x^2, or
C(x) = 16/x + 1.5x^2
Differentiate this with respect to x:
C '(x) = -16 / x^2 + 3 x
Set this equal to 0 and solve for x: -16/x^2 = -3x, or 16 = 3x^3
Then x^3 = 16/3, and x = 5 1/3 ft. We already have the formula
(x^2)h= 6 cu ft, so if x = 5 1/3, or 16/3, then (16/3)^2 h = 6, or
h = 6 / [16/3]^2.
h = 6 (9/256) = 0.21 ft. While possible, this h = 0.21 ft seems quite unlikely.
Please work through this problem yourself, making sure you understand each step. If questions arise, or if you find an error in my approach, please let me know.
Once again:
1. Write a formula for the total cost of the material used: 4 sides of dimensions xh each, plus 1 bottom, of dimensions x^2. Include the unit prices: $1 per square foot for the sides and $1.50 per square foot for the bottom.
2. Differentiate C(x) with respect to x.
3. Set C '(x) = 0 and solve for the critical value(s).
4. Calculate h from your value for x.
5. Write the dimensions of the tank: bottom: x^2; height: h
