For the first question, you need to count all of your choices. Kepp in mind, it will be a fraction. Then count all of your "V6".
12/24 = 1/2
Hope this helps!!
Let's do process of elimination
a) 2 is part of the set and 2 is not greater than 2. NO
b) 5 and 10 in the set are divisible by 5. NO
c) 2,4,6,8,10 are even but the rest are odd ( BUT note the word "or"). the rest are less than 12. YES
d) 0 and 1 are the only numbers that are neither prime nor composite (they're not even part of the set). NO
e) the square root of 9 is 3 so the maximum number is 9 (but what happened to 10?) NO
<h3>3
Answers:</h3>
A) y intercept is (0,3)
C) Axis of symmetry is x = -1
D) Vertex is (-1, 4)
So basically everything but choice B is true.
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Explanation:
Choice A is true because plugging in x = 0 leads to y = 3. Effectively, anything with an x goes away when x = 0 leaving that 3 behind. So finding the y intercept in this form is fairly fast.
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To check choices B through D, let's convert the equation into vertex form.
y = -1x^2 - 2x + 3 is in the form y = ax^2 + bx + c where
a = -1
b = -2
c = 3
The vertex is located at (h,k) such that h = -b/(2a)
Plug the values of 'a' and 'b' into the equation below
h = -b/(2a)
h = -(-2)/(2*(-1))
h = 2/(-2)
h = -1
The x coordinate of the vertex is x = -1
Then use this to find the y coordinate of the vertex
y = -1x^2 - 2x + 3
y = -1(-1)^2 - 2(-1) + 3
y = 4
The y coordinate of the vertex is 4, meaning k = 4
The vertex overall is (h,k) = (-1, 4)
This shows choice D is true, meaning choice B has to be false.
Choice C is true because the axis of symmetry is the x coordinate of the vertex. This is the vertical line that cuts the parabola into two mirrored halves. This vertical line always goes through the vertex.
Everything separated by a '+' or '-' sign separates a term so in this expression there are 2 terms
Answer:
2.4 days
Step-by-step explanation:
Time working together,t ,is
1/t = 1/a+ 1/b where a and b is the times working alone
1/t = 1/4 + 1/6
Multiply each side by 12t to clear the fractions
12t( 1/t )= 12t(1/4 + 1/6)
12 = 3t+2t
12 = 5t
Divide by 5
12/5 = 5t/5
2 2/5 =t
2.4 days
