Answer:

Step-by-step explanation:
Given


Required
Write the equation of the function 
Express the function as:

In: 

--- (1)
In 

--- (2)
Divide (2) by (1)






Substitute 5/6 for b in (1)






The function: 

Answer:
•cos(s+t) = cos(s)cos(t) - sin(s)sin(t) = (-⅖).(-⅗) - (√21 /5).(⅘) = +6/25 - 4√21 /25 = (6-4√21)/25
•cos(s-t) = cos(s)cos(t) + sin(s)sin(t) = (-⅖).(-⅗) + (√21 /5).(⅘) = +6/25 + 4√21 /25 = (6+4√21)/25
cos(t) = ±√(1 - sin²(t)) → -√(1 - sin²(t)) = -√(1 - (⅘)²) = -⅗
sin(s) = ±√(1 - cos²(s)) → +√(1- cos²(s)) = +√(1 - (-⅖)²) = √21 /5
(x,y)
x=how far to the right
y=how far up
ok so
y=mx+b
m=slope
b=y intercept or where the line intercept the y axis
it looks like the line intercept the y axis at 2 high so
y=mx+2
we look at our options and we see that there is only 1 equation that has y=mx+2
that is B
B is the answer
Answer:
This tells us that the vertex is at (−2, 9) and the equation of the axis of symmetry is x = −2. To find the x-intercepts, we put y = 0 to obtain
(x + 2)2 − 9 = 0
(x + 2)2 = 9
x + 2 = 3 or x + 2 = −3
x = 1 or x = −5.
Step-by-step explanation:
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The standard form of a quadratic equation is written as y=ax2+bx+c, where x and y are variables and a, b, and c are known constants. To find the y-intercept from a quadratic equation, substitute 0 as the value for x and solve. The y-intercept is always equal to the value of c in the equation.