3(d + 11) = 6(d + 33)
So you have: 3d + 33 = 6d + 198
which is: -3d = 165
or d = -55
So you have <em>only one answer.</em>

Factor each of the following differences of two squares and write your answer together with solution.

<h3><u>1. x² - 36</u></h3>

Rewrite
. The difference of squares can be factored using the rule:
.

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<h3><u>2. 49 - x²</u></h3>

Rewrite 49-x² as 7²-x². The difference of squares can be factored using the rule:
.

Reorder the terms.

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<h3><u>3. 81 - c²</u></h3>

Rewrite 81-c²as 9²-c². The difference of squares can be factored using the rule:
.

Reorder the terms.

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<h3><u>4</u><u>.</u><u> </u><u>m²</u><u>n</u><u>²</u><u> </u><u>-</u><u> </u><u>1</u></h3>

Rewrite m²n² - 1 as
. The difference of squares can be factored using the rule:
.

The ratio is:
Chlorine : Water = 1 : 10
m ( Water ) = 15 ounces
m ( Chlorine ) = x
x : 15 = 1 : 10
10 x = 15 * 1
10 x = 15
x = 15 : 10
x = 1.5 ounces
Answer:
We need to add 1.5 ounces of Chlorine for the correct ratio.