Answers:
- Vertex form: y = -2(x-1)^2 + 8
- Standard form: y = -2x^2 + 4x + 6
Pick whichever form you prefer.
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Explanation:
The vertex is the highest point in this case, which is located at (1,8).
In general, the vertex is (h,k). So we have h = 1 and k = 8.
One root of this parabola is (-1,0). So we'll plug x = -1 and y = 0 in as well. As an alternative, you can go for (x,y) = (3,0) instead.
Plug those four values mentioned into the equation below. Solve for 'a'.
y = a(x-h)^2 + k
0 = a(-1-1)^2+8
0 = a(-2)^2+8
0 = 4a+8
4a+8 = 0
4a = -8
a = -8/4
a = -2
The vertex form of this parabola is y = -2(x-1)^2+8
Expanding that out gets us the following
y = -2(x-1)^2+8
y = -2(x^2-2x+1)+8
y = -2x^2+4x-2+8
y = -2x^2+4x+6 .... equation in standard form
Answer: There are 97 nickels and 108 quarters.
Step-by-step explanation:
Let x = Number of nickels, y = Number of quarters.
As per given,
x+y = 205 ...(i)
0.05x+0.25y = 31.85 ... (ii) [1 nickel = $0.05, 1 quarter = $ 0.25]
Multiply (ii) by 20, we get
x+5y=637 ...(iii)
Eliminate (i) from (iii)
4y = 432
⇒ y = 108 [Divide both sides by 4]
Put value of y in (i), we get
Hence, there are 97 nickels and 108 quarters.
−15.82x + 20.042
calculated it
The first question is (7)
Answer:
5+x2
Step-by-step explanation:
