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3 years ago

Which correctly completes this number sentence?

Mathematics

2 answers:

ivolga24 [154]3 years ago

7 0

4 x (3+4) because 4x3=12 and 4x4=16
16+12=28 in which 4x7=28 since 3+4 is 7
So 4 x (3+4) would be the correct answer

Molodets [167]3 years ago

7 0

4 x (3+4) because 4x3=12 and 4x4=16

16+12=28

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I need help! f(x)=-3x+6/4x-8

tia_tia [17]

Answer:

same

Step-by-step explanation:

8 0

2 years ago

Graph f(x) =-2x^+16x-30 by factoring to find the solutions, then find the coordinates of the vertex, and the axis of symmetry. I

fredd [130]

Answer:

Observe attached image

Function zeros:

(3, 0), (5, 0)

Vertex:

(4, 2)

Axis of symmetry:

 $x =4$ 

Step-by-step explanation:

First factorize the function

$f (x) = -2x ^ 2 + 16x-30$

Take -2 as a common factor.

$-2(x ^ 2 -8x +15)$

Now factor the expression $x ^ 2 -8x +15$

You must find two numbers that when you add them, obtain the result -8 and multiplying those numbers results in 15.

These numbers are -5 and -3

Then we can factor the expression in the following way:

$f (x) = -2(x-5)(x-3)$

The quadratic function cuts the x-axis at x = 3 and at x = 5.

Now we find the coordinates of the vertex.

For a function of the form $ax ^ 2 + bx + c$ the x coordinate of its vertex is:

$x = \frac{-b}{2a}$

In the function $f (x) = -2x ^ 2 + 16x-30$

$a = -2\\b = 16\\c = 30$

Then the vertice is:

$x = \frac{-16}{2(-2)}\\\\x = 4$

The y coordinate of the symmetry axis is

$y = f (4) = -2 (4) ^ 2 +16 (4) -30\\\\y = 2$

The axis of symmetry is a vertical line that cuts the parabola in two equal halves. This axis of symmetry always passes through the vertex.

Then the axis of symmetry is the line

$x = 4$

The solutions and the vertice written as ordered pairs are:

Function zeros:

(3, 0), (5, 0)

Vertex:

(4, 2)

6 0

3 years ago

In a bag there are pink buttons, yellow buttons and blue buttons.

larisa86 [58]

Answer:

do you have any options for this question just to check??

8 0

2 years ago

PLZZZ HELPPP THIS IS A TIMED TESTTT *look at the picture*

Artyom0805 [142]

Answer:

x=14

Step-by-step explanation:

7 0

3 years ago

A boat can travel at an average speed of 10 miles per hour in still water. Traveling with the current, it can travel 6 miles in

oksano4ka [1.4K]

Answer: The speed of the current is 2 miles per hour.

Step-by-step explanation:

We know that the speed of the boat is:

S = 10 mph.

When the boat travels with the current, the speed will be:

S = 10mph + x

where x = speed of the current.

When the boat travels against the current, the speed will be:

S = 10mph - x

Now, for a given amount of time T, when the boat travels with the current, it moves a distance of 6 miles.

Then we have the equation:

(10mph + x)*T = 6mi

And against the current, in the same time the boat moves 4 mi, then:

(10 mph - x)*T = 4mi

Then we have the system of equations:

(10mph + x)*T = 6mi

(10 mph - x)*T = 4mi

Now, we can take the quotient of these two equations and get:

((10mph + x)*T)/((10 mph - x)*T) = (6mi/4mi)

(10mph + x)/(10 mph - x) = 3/2

Now we can solve this for x.

(10mph + x) = (3/2)*(10 mph - x)

10mph + x = (3/2)*10mph - (3/2)*x

x + (3/2)*x = (3/2)*10mph - 10mph

(5/2)*x = (1/2)*10mph = 5mph

x = (2/5)*5mph = 2mph.

The speed of the current is 2 miles per hour.

6 0

2 years ago

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