What is yeast and why is it used for making bread?

yeast is a micro organism

It is a fungi

it is used in making breads as it helps bread to become spongy and soft to eat.

this process is known as fermentation

a chair, a bed, and a toothbrush

explanation:

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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