Answer:
Jeff got 20 answers right.
Step-by-step explanation:
The maximum number of points Jeff can get is 100. (25 * 4) However, for each question he gets wrong, he's actually losing 6 points because he doesn't get the four points for getting right, and has the additional -2 points for getting it wrong. Since he only got a score of 70, that means he lost 30 points.
30/6 = 5. So he missed 5 question and got 20 question right.
<h2>
Answer:</h2>
Shown below
<h2>
Step-by-step explanation:</h2>
The first system of inequality is the following:

To find the solution here, let's take one point, say,
and let's taste this point into both inequalities, so:
<h3>FIRST CASE:</h3>
First inequality:

The region is not the one where the point
lies
Second inequality:

The region is the one where the point
lies
So the solution in this first case has been plotted in the first figure. As you can see, there is no any solution there
<h3>SECOND CASE:</h3>
First inequality:

The region is the one where the point
lies
Second inequality:

The region is not the one where the point
lies
So the solution in this first case has been plotted in the second figure. As you can see, there is a solution there.
CONCLUSION: Notice that when reversing the signs on both inequalities the solution in the second case is the part of the plane where the first case didn't find shaded region.
<em>Answer,</em>
<em><u>26</u></em>
<u><em>Hope This Helps :-)</em></u>