Let x = number of years between 1990 and 2000.
Rainbow smelt:
Initial population = 227
Average yearly rate of change = -19.76
The linear function that models the population is
y₁ = 227 - 19.76x
Bloater fish
Initial population = 1052
Average yearly rate of change = -92.57
The linear function that models the population is
y₂ = 1052 - 92.57x
When the two populations are equal, then y₁ = y₂.
That is
227 - 19.76x = 1052 - 92.57x
(92.57 - 19.76)x = 1052 - 227
72.81x = 825
x = 11.33 years
= 11 years, 0.33*12 months
= 11 years, 4 months
Add x to 1990 to obtain the year April 2011.
Answer:
x = 11.33 years.
This occurs in April 2001.
Q1. The answers are (–1, 8), (0, 7), (3, 18)
<span>–3x + y ≥ 7
</span>Let's go through all choices:
<span>(–2, –3)
</span>(-3) * (-2) + (-3) ≥ 7
6 - 3 ≥ 7
3 ≥ 7 INCORRECT
(–1, 8)
(-3) * (-1) + 8 ≥ 7
3 + 8 ≥ 7
11 ≥ 7 CORRECT
(0, 7)
(-3) * 0 + 7 ≥ 7
0 + 7 ≥ 7
7 ≥ 7 CORRECT
(1, 9)
(-3) * 1 + 9 ≥ 7
-3 + 9 ≥ 7
6 ≥ 7 INCORRECT
(3, 18)
(-3) * 3 + 18 ≥ 7
-9 + 18 ≥ 7
9 ≥ 7 CORRECT
Q2. The answers are:
5x + 12y ≤ 80
x ≥ 4
<span>y ≥ 0
</span>
<span>x - small boxes
</span><span>y - large boxes
</span>He has x small boxes that weigh 5 lb each and y large boxes that weigh 12 lb each <span>on a shelf that holds up to 80 lb:
5x + 12y </span>≤ 80
Jude needs at least 4 small boxes on the shelf: x ≥ 4
Let's check if y can be 0:
5x + 12y ≤ 80
5x + 12 * 0 ≤ 80
5x + 0 ≤ 80
5x ≤ 80
x ≤ 80 / 5
x ≤ 16
x ≥ 4 can include x ≤ 16
So, y can be 0: y ≥ 0
For this, you have to understand the ratios of a 30,60,90 triangle. The ratio(in order) is x, x(sqrt 3), 2x (following the 30,60,90 pattern y'know). Well, we know the length of the hypotenuse, 4.2, so let's use ratios to figure the other sides out. The ratio of AC is x and the ratio of AB is 2x, so 2x/2=x=2.1. One side down. BC has a ratio of x(sqrt 3). We already know x so we can substitute it in. We get 2.1(sqrt 3). To calculate the area, use the formula 1/2(bh). Inputting the values in, we get 1/2(2.1*(2.1(sqrt 3)). This can be calculated to around 3.82. To calculate the perimeter, take the sum of the sides. By adding the sides together, we get about 9.98. Hope you can now understand how to do these kinds of questions.
Answer:
A. is Inverse correlation and B. is More money
Step-by-step explanation:
A. the relationship is inverse, which means that the more weeks had past, the less he spent
B. Since he is spending less money each week and he earns the same amount, this means that he is saving more money
