1. If the average (arithmetic mean) of g and 100 is 75, what is the value of g + 100?
A. 50
B. 125
C. 150 Correct
D. 175
Explanation
<h2>g + 100 equals 150.</h2>
To find the value of g + 100, we first determine g using the given average. The average of g and 100 is calculated as (g + 100) / 2, which equals 75. By solving for g, we can then easily calculate g + 100.
<b>A) 50</b>
This choice suggests that g + 100 equals 50, which would imply that g is -50. However, this contradicts the given average of 75, as substituting g = -50 into the average formula yields a negative result, which is inconsistent with the arithmetic mean calculated from positive numbers.
<b>B) 125</b>
If g + 100 were 125, it would mean that g is 25. Substituting g = 25 into the average formula results in (25 + 100) / 2 = 62.5, which does not match the stated average of 75. Thus, this choice is incorrect.
<b>C) 150</b>
This is the correct choice. If g + 100 equals 150, then g must be 50. Substituting g = 50 into the average formula gives (50 + 100) / 2 = 75, which confirms that this option satisfies the condition provided in the question.
<b>D) 175</b>
If g + 100 were 175, it would imply g is 75. Calculating the average with g = 75 results in (75 + 100) / 2 = 87.5, which is not equal to the specified average of 75. Therefore, this option is also incorrect.
<b>Conclusion</b>
To solve for g + 100, we start with the average equation (g + 100) / 2 = 75 and find that g must equal 50. This leads directly to the conclusion that g + 100 equals 150, confirming that choice C is the accurate answer, while all other options fail to satisfy the initial average condition.
2. Which of the following inequalities is graphed in the xy-plane above?
A. x≤y≤3x
B. x≥y≥3x
C. −x≤y≤3x Correct
D. −x≥y≥3x
Explanation
<h2>–x ≤ y ≤ 3x</h2>
This inequality describes a region in the xy-plane where the value of y is bounded above by the line y = 3x and below by the line y = -x. The graphical representation shows that y must satisfy both conditions simultaneously, creating a triangular region between these two lines.
<b>A) x ≤ y ≤ 3x</b>
This inequality suggests that y is greater than or equal to x and less than or equal to 3x. The line y = x would be the lower boundary, which does not match the graphical representation, as the lower boundary is actually y = -x. Therefore, this choice is incorrect as it misrepresents the lower limit of y.
<b>B) x ≥ y ≥ 3x</b>
This option indicates that y is less than or equal to x and greater than or equal to 3x. This scenario is impossible because y cannot be both less than or equal to x and greater than or equal to 3x simultaneously. The concept defines an invalid region, making this choice incorrect.
<b>D) –x ≥ y ≥ 3x</b>
This inequality implies that y is less than or equal to –x and greater than or equal to 3x. Similar to option B, this combination is also impossible; y cannot simultaneously be below –x and above 3x. Thus, this choice does not reflect the region depicted in the graph.
<b>Conclusion</b>
The correct inequality, –x ≤ y ≤ 3x, accurately captures the graphical representation in the xy-plane, delineating a region where y fluctuates between the lines y = -x and y = 3x. The incorrect options either misinterpret the boundaries or present logically impossible scenarios, underscoring the importance of understanding inequalities in graphical contexts.
3. In the inequalities, a and b are integers. What is the least integer value of a/b​? −5≤a≤5 1<b<5
A. 2
B. -1
C. -2 Correct
D. -4
Explanation
<h2>-2</h2>
To determine the least integer value of \( \frac{a}{b} \) given the inequalities \( -5 \leq a \leq 5 \) and \( 1 < b < 5 \), we must examine the possible values for \( a \) and \( b \). The integer \( b \) can take values of 2, 3, or 4, and we need to find the minimum ratio \( \frac{a}{b} \).
<b>A) 2</b>
The integer value of 2 can be achieved by taking \( a = 4 \) and \( b = 2 \), resulting in \( \frac{4}{2} = 2 \). However, this is not the least integer value since there are combinations that yield a smaller ratio.
<b>B) -1</b>
To achieve a ratio of -1, one would need \( a = -2 \) and \( b = 2 \), resulting in \( \frac{-2}{2} = -1 \). While this is a valid option, it is not the least integer value obtainable from the given ranges.
<b>C) -2</b>
Choosing \( a = -4 \) and \( b = 2 \) gives \( \frac{-4}{2} = -2 \), which is indeed the least integer value for \( \frac{a}{b} \) within the specified constraints. No other combination provides a smaller value than -2.
<b>D) -4</b>
For \( \frac{a}{b} = -4 \), one would need \( a = -4 \) and \( b = 1 \). However, since \( b \) must be greater than 1, this combination is invalid. Thus, -4 cannot be achieved under the given constraints.
<b>Conclusion</b>
The least integer value of \( \frac{a}{b} \) determined from the inequalities \( -5 \leq a \leq 5 \) and \( 1 < b < 5 \) is -2. This is found by selecting appropriate integer values for \( a \) and \( b \) that satisfy all conditions, demonstrating that while other options exist, -2 remains the minimum achievable ratio.
4. Which of the following represents all values of x that satisfy the inequality - 1 <= 4x - 5?
A. 1755845659cA.png Correct
B. 1755845713cB.png
C. 1755845777cC.png
D. 1755845819cD.png
Explanation
<h2>A) 1755845659cA.png</h2>
To satisfy the inequality -1 <= 4x - 5, we can rearrange it to find the range of values for x. Solving the inequality gives us x ≥ 1, which corresponds to the correct graphical representation showing all values greater than or equal to 1.
<b>B) 1755845713cB.png</b>
This option likely represents a range of values that do not include x = 1 or greater, which does not satisfy the inequality. The graphical representation must show values that include all numbers starting from 1 and extending to infinity to be correct.
<b>C) 1755845777cC.png</b>
This choice probably depicts values that either start below 1 or do not encompass the entire range required by the inequality. An appropriate solution would need to clearly include all values from 1 onward, which this option fails to show.
<b>D) 1755845819cD.png</b>
This option likely represents values that either cap off before reaching 1 or incorrectly includes values less than 1. The inequality clearly specifies that x must be greater than or equal to 1, which this representation does not meet.
<b>Conclusion</b>
In solving the inequality -1 <= 4x - 5, we find that x must be greater than or equal to 1. The correct representation of this solution is shown in option A, which includes all values of x from 1 to infinity. The other options fail to encompass this critical range, making them incorrect for the given inequality.
5. Which of the following is an equation of the line graphed above?
A. y=−31​x+1
B. y=31​x−1 Correct
C. y=3x-1
D. y=-3x-9
Explanation
<h2>y=31x−1 represents the equation of the line graphed above.</h2>
The equation of the line indicates a slope of 31 and a y-intercept of -1, which matches the visual representation on the graph, confirming that this is the correct choice among the options provided.
<b>A) y=−31x+1</b>
This equation features a slope of -31, which implies that the line would descend steeply from left to right. However, the line graphed rises steeply instead, indicating a positive slope, thus making this option incorrect.
<b>B) y=31x−1</b>
This equation accurately depicts a line with a steep positive slope of 31 and a y-intercept at -1. Both characteristics correspond perfectly with the visual representation of the line on the graph, confirming its correctness.
<b>C) y=3x-1</b>
While this equation has the correct y-intercept of -1, the slope of 3 is too shallow compared to the steepness of the graphed line. The line represented by this equation would not match the steep incline visible in the graph, rendering this option incorrect.
<b>D) y=−3x−9</b>
This equation has a negative slope of -3, indicating a downward trend from left to right, which contradicts the positive trend of the line depicted in the graph. Additionally, the y-intercept of -9 is far below the actual intercept observed, making this option incorrect.
<b>Conclusion</b>
Among the options provided, only y=31x−1 accurately represents the equation of the line shown in the graph. It possesses both the correct positive slope and y-intercept, aligning perfectly with the line's trajectory. The other choices either misrepresent the slope or y-intercept, thereby confirming that they do not correspond to the graphed line's properties.