All you wanna do is get 'y' by itself so you divide 80 by -5 and you get -16 as the answer
Answer:
8
Step-by-step explanation:
The law of cosines can be helpful here. The largest angle (C) will be opposite the longest side (c). That law tells us ...
... c² = a² + b² -2ab·cos(C)
Then
... cos(C) = (a² +b² -c²)/(2ab)
We don't actually need the angle. We only need to know the sign of the cosine.
... cos(C) = (7² +15² -17²)/(2·7·15) = -15/210 . . . . negative sign, so C > 90°
The sail has the shape of an obtuse triangle.
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A triangle solver app on your calculator, phone, tablet, or computer can give you the result easily.
Answer:
y = (x - 2)² - 9 Vertex form
y = x² - 4x - 5 Standard form
Step-by-step explanation:
vertex = (h, k) = (2, -9)
Vertex form
y = a(x - h)² + k
y = a(x - 2)² - 9
find "a" using point (5, 0)
0 = a(5 - 2)² - 9
0 = a(3)² - 9
0 = 9a - 9
9 = 9a
a = 1
y = (x - 2)² - 9
Standard form
y = (x² - 4x + 4) - 9
y = x² - 4x - 5