What system of linear inequalities is…

Mathematics Questions

What system of linear inequalities is represented by the following graph on a coordinate plane: a solid line with a positive slope through (0, -2) and (2, 0) with the area to the left shaded, and a dashed line with a negative slope through (0, 2) and (4, 0) with the area below and to the left shaded? A. y > x – 2 and x – 2y < 4 B. y > x + 2 and x + 2y < 4 C. y > x – 2 and x + 2y < 4 D. y > x – 2 and x + 2y < -4

Short Answer

The process involves identifying two inequalities: the first is ( y geq x – 2 ) with a solid line representing the area above it, and the second is ( y < -frac{1}{2}x + 2 ) with a dashed line indicating the area below. The complete system of inequalities can be expressed as ( y geq x - 2 ) and ( x + 2y < 4 ), which can be visualized on a graph to show the shaded regions.

Step-by-Step Solution

Step 1: Determine the First Inequality

Start by identifying the first inequality which is given as ( y geq x – 2 ). To find the equation of the line, use the points (0, -2) and (2, 0) to calculate the slope. The slope formula is ( m = frac{y_2 – y_1}{x_2 – x_1} ). By substituting the given points, you find that the slope ( m = 1 ) and the y-intercept is -2. Thus, the equation of the line is ( y = x – 2 ) and you will shade the area to the left of the solid line.

Step 2: Determine the Second Inequality

Next, for the second inequality, we use the points (0, 2) and (4, 0) to find its equation. Again apply the slope formula ( m = frac{y_2 – y_1}{x_2 – x_1} ), yielding a slope of ( m = -frac{1}{2} ) and a y-intercept of 2. The equation of this dashed line is ( y = -frac{1}{2}x + 2 ). Since we are looking at values below this line, the inequality is ( y < -frac{1}{2}x + 2 ).

Step 3: Combine and Rewrite the System of Inequalities

Finally, combine the results from the first two steps to write the complete system of inequalities. Start by rewriting the second inequality ( y < -frac{1}{2}x + 2 ) as ( 2y < -x + 4 ) leading to ( x + 2y < 4 ). Therefore, your complete set of inequalities is ( y geq x - 2 ) and ( x + 2y < 4 ). Make sure to visualize this on a graph to clearly identify the shaded regions.

Related Concepts

First inequality

A mathematical expression that sets a lower or upper limit for the variable, such as ( y geq x – 2 ) in the given context.

Slope

A measure of the steepness or incline of a line, calculated using the formula ( m = frac{y 2 – y 1}{x 2 – x 1} ) to determine how much ( y ) changes for a unit change in ( x ).

System of inequalities

A set of two or more inequalities involving the same variables, which collectively define a solution set that can be represented graphically.

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