Answer:
B. (-0.73, 0), (2.73, 0)
Step-by-step explanation:
vertex form of a parabola
y = a(x-h)^2 +k
y = a(x-1)^2 -9
substitute the point in to find a
-6 = a (0-1) ^2 -9
-6 = a *1 -9
add 9 to each side
-6+9 = a -9+9
3 =a
y = 3(x-1)^2 -9
FOIL
y = 3(x-1)(x-1) -9
y = 3(x^2-2x+1) -9
distribute
y = 3x^2-6x+3-9
combine like terms
y = 3x^2 -6x -6
factor out 3
y= 3(x^2 - 2x -2)
set = 0
0 = 3(x^2 - 2x -2)
x^2 - 2x -2 =0
using the quadratic formula
-b±sqrt(b^2 -4ac)
----------------------
2a
-(-2) ± sqrt(2^2 - 4(1)(-2))
-------------------------------
2(1)
2 ± sqrt(4+8)
------------------
2
2±sqrt(12)
---------------
2
2±2sqrt(3)
----------------
2
1±sqrt(3)
roots: 2.73, and -.73
Answer:
x = 15 cm
Step-by-step explanation:
All the ratio of corresponding sides should be equal
10 corresponds to x
16 corresponds to 24
12 corresponds to 18
<em>Finding the ratio of the known pairs:</em>
<em>Similarly 10 is to x should be 2 is to 3. Finding x:</em>
So x = 15.
Answer:
Letter c
Step-by-step explanation:
You are distributing the 7 to each term in the parentheses.
7(8x) is 56 x
Here is the tricky part. You can think of it a couple of ways:
7(-4y) = -28y a positive times a negative is a negative.
or 7(4y) = 28 , but then remember that you are subtracting so it will become -28
7(6) = 56
56x - 28y +42
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