Scientists use existing fossils to predict what the transitional forms between organisms might look like. Why might it be so hard for scientists to find fossils of these transitional forms

Any preserved remains, trace, or impression of any once-thriving living thing from the past geological age is known as a fossil. This comprises exoskeletons, bones, stone imprints of animals or microbes, shells, hair, petrified wood, objects preserved in amber, DNA remnants, coal, and oil. The fossil record is the term used for the totality of fossils.  

The scientists use the prevailing fossils to show what the intermediary forms between the organisms may appear like. It is hard for the scientists to locate the fossils of the transitional forms as the formation of the fossils of the transitional forms may have never taken place because of the environmental conditions. In case if they did have formed, then the natural procedures like erosion may have demolished them.  

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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