Using the law os cosines formula b^2 = a^2 + c^2 - 2*a*c*cos(B)
a = 17, b = 8, c = 16
8^2 = 17^2 + 16^2 - 2*17*16* cos(B)
64 = 289 + 256 - 544 * cos(B)
544*cos(B) = 289 + 256 - 64
544 * cos(B) = 481
cos (B) = 481/544
B = arccos(481/544)
B = 27.8 degrees
The required equation is m = 100-5c.
An equation is a mathematical statement that shows that two mathematical expressions are equal.
Given that, Grace has $100. She is buying charms for her bracelet that cost $5 each.
Let, she buys c charms for her bracelets,
Therefore, the equations become,
m = 100-5c
Where, m is money is she left with.
Hence, the required equation is m = 100-5c.
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