How do you solve $2^(3x)=64$ using a graph?

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Answer 1 · 2017-02-25T09:32:34

The solution is $x=2$

To solve the equation $2^(3x)=64$ ,

one should draw the graph of $y=2^(3x)-64$

It is apparent that as $x->-oo$ , $2^(3x)->0$ and $y->-64$

Some other values will be when $x=0$ $y=-64$ ; when $x=1$ $y=-56$ ; when $x=4/3$ $y=-48$ and when $x=5/3$ $y=-32$

and graph appears as follows:
graph{2^(3x)-64 [-4, 4, -75, 75]}

As the graph intersects $x$ -axis at $(2,0)$

the solution is $x=2$

How do you solve 2^(3x)=642^(3x)=64 using a graph?