Answer:
D) 20 ≤ x ≤ 50.
Step-by-step explanation:
Given : , the maximum speed is 50 miles per hour, and the minimum speed is 20 miles per hour.
To find: Write a compound inequality that represents the situation.
Solution : We have given that
Maximum speed = 50 miles per hour.
Minimum speed = 20 miles per hour.
Let x represent the speed .
According to question
maximum speed is 50 or less than 50.
Then we will use less than equal to sing
x ≤ 50
For Minimum speed is 20 or greater than 20 .
x ≥ 20
On combining both statement,
20 ≤ x ≤ 50
Therefore, D) 20 ≤ x ≤ 50.
No.
When trying to analyze an overall satisfaction with Quality of service. The number of population he is analyzing should not be limited to a certain factor. This would cause a narrow data information gather and would not represent the entire population. The surveys should be based randomly to avoid data bias/filters and actual results would be realistic.
The number of hard puzzles solved by Tina using a system of equations is 15
Using the relation :
The system of equation representing the scenario can be written thus :
a + b = 50 - - - - - (1)
30a + 60b = 1950 - - - - (2)
From (1)
a = 50 - b - - - - - - (3)
Substitutea = 50 - b in (2)
30(50 - b) + 60b = 1950
1500 - 30b + 60b = 1950
1500 + 30b = 1950
30b = 1950 - 1500
b = 450 / 30
b = 15
Therefore, the Number of hard puzzles solved is 15
Learn more :brainly.com/question/18796573
This is a system of equations. We can solve it by recognizing the two linear equalities we've given to solve this equation.
First, let's start off by recognizing two variables: x and y. x will be our number of hard puzzles, and y will be our number of easy puzzles. We're given that the number of hard puzzles and easy puzzles sum to 50, so we can rewrite that as:
Next, we're given that the sum of the points gained from the hard puzzles (60x), and the number of points gained from the easy puzzles (30y), sum to 1950. We can rewrite that as:
Now, we have our two linear equations, and we must solve for the hard puzzles, so x. Solving for the hard puzzles means eliminating the easy puzzles from our systems, so we can multiply our first equation by 30, and subtract it from the first equation. This is a technique called elimination.
Since x=15, Tina has solved 15 hard puzzles.
Answer:
d c a
Step-by-step explanation:
-2x+5y=-12
-6x+____y=____
solve quadratic formula the first x is squared
x-2x-15=0