What is the missing step in this proof?
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Anabel uses 10 gallons of gas to drive 220 miles on the highway. if she travels at the same rate, how many miles can she drive on 7 gallons of gas

Which is a true statement comparing the graphs of x^2/6^2-y^2/8^2 = 1 and x^2/8^2-y^2/6^2 the foci of both graphs are the same points. the lengths of both transverse axes are the same. the directrices of = 1 are horizontal while the directrices of = 1 are vertical. the vertices of = 1 are on the y-axis while the vertices of = 1 are on the x-axis.

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?