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2 years ago

The axis of symmetry for the graph of the function f(x) = 3x2 + bx + 4 is x = . What is the value of b?

2 answers:

6 0

The value of b is one. You just have to use the standard equation y = a + bx^2 + c. Get a, b, then c and from the given equation above you can derive a formula which is x is equal to the - b over 2 multiplied by a. if you get the value of x then substitute it to the equation and you will now get the value of b.

Mila [183]2 years ago

3 0

Answer:

b = ±i

Step-by-step explanation:

Given the axis of symmetry of the equation f(x) = 3x²+bx+4 is x= b, to get the value of b we will substitute x = b into the equation and equate to zero as shown:

at f(b) = 0

f(b) = 3b² + b(b) + 4 = 0

3b²+b² + 4 = 0

4b² = -4

b² = -4/4

b² = -1

b = √-1

b = ±i

The value of b is a complex number ±i

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A car salesman earns a 20% commission on every car that he sells. Approximately what commission would he make if he sold a car f

GREYUIT [131]

C I'm pretty sure even though the real answer is 1979 so its d or c

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2 years ago

Can anyone get this answer

Doss [256]

This problem is asking you to apply the *Pythagorean Theorem*, given the information you’ve been given.

In case you’ve forgotten, the Pythagorean Theorem states that, in any given right triangle, the sum of the squares of the lengths of its legs is equal to the square of the length of its hypotenuse (the side opposite its right angle). If we call the lengths of the legs a and b, and the length of the hypotenuse c, this can be expressed in notation as a^2+b^2=c^2 (it doesn’t matter in this case which leg you pick for a and which you pick for b). Here, if we choose the left leg as a and the bottom leg as b, we’re given that a^2 (the area of a square with sides of length a) is 25 sq. in, and b is 3.5 in. Plugging those values into the equation, we have:

25 + (3.5)^2 = c^2

From here, you don’t even need to solve for c, you just need to find the value of c^2 (since you’re trying to find the area of a square with side lengths c). Just solve the left side of the equation, and you’ll have your answer in square inches.

7 0

2 years ago

1)a chord of length 18cm midway the radius of a circle. calculate the radius of the circle correct to 1d.p. 2)if two parallel ch

kykrilka [37]

Part 1:

Given that the length of the chord is 18 cm and the chord is midway the radius of the circle.

Thus, half the angle formed by the chord at the centre of the circle is given by:

$\cos\theta=\frac{\left( \frac{1}{2} r\right)}{r}= \frac{1}{2} \\ \\ \Rightarrow\theta=\cos^{-1}\left( \frac{1}{2} \right)=60^o$

Now,

$\sin60^o= \frac{9}{r} \\ \\ \Rightarrow r= \frac{9}{\sin60^o} =10.392$

Therefore, the radius of the circle is 10.4 cm to 1 d.p.

Part 2I:

Given that the radius of the circle is 10 cm and the length of chord AB is 8 cm. Thus, half the length of the chord is 4cm. Let the distance of the mid-point O to /AB/ be x and half the angle formed by the chord at the centre of the circle be θ, then

$\sin\theta= \frac{4}{10} = \frac{2}{5} \\ \\ \theta=\sin^{-1}\left( \frac{2}{5} \right)=23.6^o$

Now,

$\cos23.6^o= \frac{x}{10} \\ \\ \Rightarrow x=10\cos23.6^o=9.165\approx9.2cm$

Part 2II:

Given that the radius of the circle is 10cm and the angle distended is 80 degrees. Let half the length of chord CD be y, then:

$\sin40^o= \frac{y}{10} \\ \\ \\ \Rightarrow y=10\sin40^o=6.428$

Thus, the length of chord CD = 2(6.428) = 12.856 which is approximately 12.9 cm.

3 0

2 years ago

Ridah has a triangular garden with the sides 28m, 15m and 41m. She has planted rose and marigold plants in her garden. She used

Mama L [17]

Answer:

70m²

Step-by-step explanation:

Area of the plot=½×28×15

= 210m²

Area used by rose plants=⅔×210 =140m²

Area used by marigold=210-140

=70m²

6 0

2 years ago

I need help please with this math problem

Arada [10]

When the dilation is centered on the origin, you can multiply each of the individual coordinates by the scale factor.

All the coordinates are ±5 and the scale factor is 1/5. Multiplying those gives ±1. The only selection with all coordinates being ±1 is
.. Selection A.

You can check to see if the signs agree in detail. (They do.)

8 0

2 years ago