What is the value of m?
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So for this we will be doing proportions, and the equation will look like this:
[tex] \frac{m}{7} =\frac{18}{m} [/tex]
So firstly, cross multiply. Your equation should look like this: [tex] m^2=126 [/tex]
Next, square root each side, and then your answer should be [tex] m=\sqrt{126} [/tex]
In short, the answer is D.