In 8 weeks the reef grows 13 m, or 104 m.
Converting 104 m into mm:
104 m 1000 mm
--------- * ------------- = 104,000 mm
1 1 m
Hi!
<h3>Isolate x on one side in either of the equations. </h3>
x + 6y - 6y = 15 - 6y
x = 15 - 6y
<h3>Now put the value of x in the other equation. </h3>
-15 + 6y + 4y = 5
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<h3>Simplify</h3>
-15 + 10y = 5
<h3>Add 15 to both sides</h3>
-15 + 15 + 10y = 5 + 15
10y = 20
<h3>Divide by 10 on both sides</h3>
10y/10 = 20/10
<u>y = 2</u>
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<h3>Now put the value of y in to solve for x. </h3>
x + 6 * 2 = 15
x + 12 = 15
x + 12 - 12 = 15 - 12
<u>x = 3</u>
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<h2>The answer is y = 2 and x = 3</h2>
Hope this helps! :)
-Peredhel
Log N^3 = 3 log N
using the theorem log a^2 = 2 log a