SOLUTION: If {{{ 4m^2+9n^2=1 }}} and {{{ (2m-3n)^2=13 }}}, what is the value of mn?

Question 970352: If and , what is the value of mn?
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!

Step 1) Expand out the second equation using the distributive property or FOIL.

Step 2) Use the first equation to simplify.

Step 3) Isolate mn.

Using the idea

Distributive property

Distributive property

Combine like terms

Regrouping terms (associative property of addition)

Replace with 1 (valid since )

Now we solve for mn.

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