Find the vertex: -4x^2 + 16x - 7
Vertex = ( x, f(x)).
x = -b/2a
x = -16/2(-4)
x = -16/-8
x = 2
f(x) = -4x^2 + 16x - 7
Let x = 2
f(2) = -4(2)^2 + 16(2) - 7
f(2) = -4(4) + 32 - 7
f(2) = -16 + 32 - 7
f(2) = 16 - 7
f(2) = 9
Vertex = (2, 9)
Step-by-step explanation:
Given that,
DE = 8x - 13
EF = 5x + 17
DF = x + 21
Also,
DE = EF
which means that,
8x - 13 = 5x + 17
8x - 5x = 17 + 13
3x = 30
x = 30/3
x = 10
Now,
DE = 8x - 13 = 8×10 - 13 = 80 - 13 = 67cm
EF = 5x + 17 = 5×10 + 17 = 50 + 17 = 67cm
DF = x + 21 = 10 + 21 = 31cm
(cube root of 5) * sqrt(5)
--------------------------------- = ?
(cube root of 5^5)
This becomes easier if we switch to fractional exponents:
5^(1/3) * 5^(1/2) 5^(1/3 + 1/2) 5^(5/6)
------------------------ = --------------------- = ------------- = 5^[5/6 - 5/3]
[ 5^5 ]^(1/3) 5^(5/3) 5^(5/3)
Note that 5/6 - 5/3 = 5/6 - 10/6 = -5/6.
1
Thus, 5^[5/6 - 5/3] = 5^(-5/6) = --------------
5^(5/6)
That's the correct answer. But if you want to remove the fractional exponent from the denominator, do this:
1 5^(1/6) 5^(1/6)
---------- * ------------- = -------------- (ANSWER)
5^(5/6) 5^(1/6) 5
Answer:
The answer is 3 and (-4).
Step-by-step explanation:
We are given an equation 2x² + 2x – 24.
Let us assume that the equation is equal to zero.
2x² + 2x – 24 = 0
Now, divide whole equation by 2 we get,
x² + x – 12 = 0
x² + 4x – 3x – 12 = 0
x(x + 4) – 3(x + 4) = 0
(x – 3) (x + 4) = 0
x = 3, -4
Thus, The actual roots of f(x) are 3 and (-4).
