The first step I would take is
.. Multiply both sides of the equation by 1/4.
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You could start by adding 16 to both sides of the equation, to make the left side the square (2x +4)^2.
Answer:
f = -3/4
Step-by-step explanation:
13f + 6 -f = -3
Combine like terms
12f +6 = -3
Subtract 6 from each side
12f+6-6 = -3-6
12f = -9
Divide each side by 12
12f/12 = -9/12
f = -3/4
Each person gets about 9.75 ounces of ice cream