Y=(2/3)x+[anything] cause the thing before x is slope
The figures are similar, so the corresponding sides are proportional.
For example, the ratio of BD to HF could be 2:1 meaning BD is twice as long as HF. We could have BD = 10 and HF = 5 for instance.
The other sides would be in the same proportion to keep the figures similar. So another example would be ND/TH = 2/1
Answer:
If x=5, the solution would be 3.
The second one doesn't represent a function, because for some values of "x", you get two different values for "y" (which should not happen, if that were a function).
In every function, you must have a
single "y" value for each "x" in the domain.
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In order to see it better, you can trace a vertical line onto that graph.
If that line and the graph intersects in more than one point, then that graph doesn't represent a funcion.
Look into the attached picture and see. That vertical red line and the graph intersects in two distinct points. Therefore, it can't represent a function.
Any doubt? Please, comment below.
I hope it helps. :-)