# Khan/khan-exercises

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 Inequalities on a number line
rand( 6 ) > 0 ? randRange( 1, 9 ) : 0 rand( 3 ) > 0 ? (randRange( 1, 9 ) / 10) : 0
(INT === 0 ? "" : randFromArray(["", "-"])) randFromArray([ "<", ">", "≤", "≥" ]) REL === "≤" || REL === "≥" REL === "<" || REL === "≤" randVar() shuffle([ "direction", "inclusion", "positivity", "quantity", "none" ]) \$.inArray( "none", LINE_ERROR_TYPES ) [ "A", "B", "C", "D", "E" ] LINE_LABELS[ CORRECT_LINE_INDEX ]

Which graph on the number line represents VARIABLE_NAME REL SIGN + ( INT + FRAC )?

numberLineWithArrowAndMistakes( label, SIGN, INT, FRAC, LESS_THAN, INCLUSIVE, LINE_ERROR_TYPES, index );
Graph LINE_SOLUTION
1. Graph label

First, draw a number line with at least a few numbers on each side of SIGN + ( INT + FRAC ).

// Draw number line only numberLineWithArrowAndMistakes( null, SIGN, INT, FRAC, LESS_THAN, INCLUSIVE, LINE_ERROR_TYPES, CORRECT_LINE_INDEX ); arrow.hide(); pt.hide();

Since VARIABLE_NAME REL SIGN + ( INT + FRAC ), draw a full circle at SIGN + ( INT + FRAC ) to show that the inequality includes SIGN + ( INT + FRAC ).

Since VARIABLE_NAME REL SIGN + ( INT + FRAC ), draw an empty circle at SIGN + ( INT + FRAC ) to show that the inequality does not include SIGN + ( INT + FRAC ).

pt.show();

Now draw an arrow to the left of the circle to include all numbers less than SIGN + ( INT + FRAC ).

Now draw an arrow to the right of the circle to include all numbers greater than SIGN + ( INT + FRAC ).

arrow.show();

This looks like it matches the arrow and circle from Graph LINE_SOLUTION above.

Determine the inequality represented by this graph on the number line:

numberLineWithArrowAndMistakes( null, SIGN, INT, 0, LESS_THAN, INCLUSIVE, LINE_ERROR_TYPES, CORRECT_LINE_INDEX );

VARIABLE_NAME REL SIGN + INT

The arrow is pointing to the left of SIGN + INT, so everything less than SIGN + INT is included.

The arrow is pointing to the right of SIGN + INT, so everything greater than SIGN + INT is included.

The circle is filled in, so SIGN + INT itself is also included.

The circle is not filled in, so SIGN + INT itself is not included.

The graph represents VARIABLE_NAME RELSIGN + INT