Answer:
17.2°
Explanations
To find angle A, use the cosine rule.
a^2 = b^2 + c^2 - 2 × a × c cos A
4^2 = 7^2 + 10^2 - 2 × 7 × 10 cos A
16 = 49+ 100 - 140 × cosA
16 = 149 - 140cosA
16- 149 = - 140cosA
-133 = - 140cosA
cosA = 133/140
cosA = 0.95
A = 17.2°
Answer:
Length: 5 ft; width: 4 ft.
Step-by-step explanation:
A = LW formula for area of rectangle
(2x + 1)(2x) = 20 substitute length, width, and area into formula
4x² + 2x - 20 = 0 use the distributive property to multiply out left side
2x² + x - 10 = 0 divide both sides of equation by 2
(2x + 5)(x - 2) = 0 factor out trinomial
2x + 5 = 0 or x - 2 = 0 use zero product rule to solve for x
2x = -5 or x = 2 subtract 5 from both sides; add 2 to both sides
x = -5/2 or x = 2
We discard x = -5/2 since it would give negative length and width, and the length and width cannot be negative.
Length: 2x + 1 = 2(2) + 1 = 5
Width: 2x = 2(2) = 4
Length: 5 ft; width: 4 ft.
Answer: the mean should not change.
Stabilizing selection: it is one type of the natural selection..
an intermediate variant selected by the nature has more survival rate against extreme and low variants. such variants are well adopted by the population and pass it for several generations without changes. it shows that the mean of the variant <span>will be stabilized for several generations</span>
Answer:16.5
Step-by-step explanation: