9514 1404 393
Answer:
3. B (1, -7)
4. B x < -4
Explanation:
3. An ordered pair is a solution to a set of equations or inequalities when putting the x and y values into each expression makes the expression true.
Here, all of the y-values offered are less than 2, so we need to look at whether the given points satisfy the second inequality.
A 0 -(-5) > 5 ⇒ 5 > 5 . . . FALSE
B 1 -(-7) > 5 ⇒ 8 > 5 . . . True
C -3 -(-4) > 5 ⇒ 1 > 5 . . . FALSE
The point (1, -7) satisfies both inequalities, so is a solution of the system.
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4. The boundary line of an inequality is solid when the "or equal to" case is included in the solution. The symbols used for that are ≤ or ≥. When the symbol is < or >, the "or equal to" case is not included, and the boundary line is dashed.
Here, you can answer the question based simply on the < symbol. There is only one inequality shown that will have a dashed boundary line: choice B.
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On a usual graph, x-values increase to the right, and y-values increase in the up direction. This means lesser values of x or y are to the left or down. You can determine the side of a boundary line that is shaded by considering this fact.
All you really need to do is find a variable term with a positive coefficient and look at where it stands in relation to the inequality symbol. Here, we have ...
x < (something)
This tells us the shading will be where x-values are less than (left of) those on the boundary line.
So, for x < -4, shading will be to the left of the dashed boundary line.