1. 4x + y>4

2. 3x - 4y < 12

3. You have at least $30 in change in your drawer, consisting of dimes and quarters. Write an inequality that shows the different number of coins in your drawer.

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- Mar 26th 2007, 11:48 PMPatiencesolve and Graph the inequalities
1. 4x + y

__>__4

2. 3x - 4y < 12

3. You have at least $30 in change in your drawer, consisting of dimes and quarters. Write an inequality that shows the different number of coins in your drawer. - Mar 27th 2007, 12:07 AMJhevonQuote:

1. 4x + y__>__4

y >= -4x + 4

this is a straight line with slope -4 and y-intercept 4. we want all values above this line. see graph1 below

Quote:

2. 3x - 4y < 12

-4y < -3x + 12

y > (3/4)x - 3 .........since i divided both sides by a negative number, i turn around the inequality sign

now this is a line with slope 3/4 and y-intercept -3. we want all values above that line. see graph2 below

Quote:

3. You have**at least**$30 in change in your drawer, consisting of dimes and quarters. Write an inequality that shows the different number of coins in your drawer.

let x be the number of dimes in the drawer

let y be the number of quarters in the drawer, then

0.10x + 0.25y >= 30 - Mar 27th 2007, 12:20 AMearboth
Hello, Patience,

to 1.:

4x + y ≥ 4 ==> y ≥ -4x + 4

y**=**-4x + 4 is a straight line. With your inequality you are looking for those points of the coordinate plane which are**above**this line. The graph of the inequality is a half plane where the border (= the straight line) is included to the half plane. (yellow + orange)

to 2.:

3x - 4y < 12 ==> y > 3/4*x - 3

You get a half plane too which is above the straight line but the border doesn't belong to the half plane! Therefore the straight line is dotted. (orange + brown)

EB