Solve the equation using mental math.

Mathematics

2 answers:

Umnica [9.8K]2 years ago

4 0

I guess answer should be C

ki77a [65]2 years ago

3 0

Answer is C. 3 start fraction 5 over 7 end fraction.

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Convert the equation (y + 2) = –1/3(x – 4) to the point-slope form. Then fill in the blanks below to describe how to graph the e

alisha [4.7K]

The point-slope form of the equation of the line is:

(y - y1) = m (x - x1)

So, (y + 2) = - 1/3 (x - 4) in the point-slope form is:

[y - (-2) ] = (-1/3) [ x - 4 ]

You must, then realize that the line passes through the point (4,-2) and its slope is - 1 /3.

That slope, -1 / 3, means that the function is decresing (because the slope is negative), and it decreases one unit when x increases 3 units.

Now you can fill in the blanks in this way:

Plot the point (4, -2), move 1 unit down, and 3 units over to find the next point on the line.

7 0

3 years ago

A running track in the shape of an oval is shown. The ends of the track form semicircles. A running track is shown. The left and

serg [7]

Two shapes.. a circle and a rectangle. The width of the rectangle serves as the diameter of the circle.
Length = 140 m ; Width = 68 m
Circumference of a circle = 2 π r circumference of a cirlce = 2 * 3.14 * (68m/2) = 2 * 3.14 * 34 m = 213.52
length = 2 * 140 m = 280 m
perimeter of the oval = 213.52 m + 280 m = 493.52 m

8 0

3 years ago

Read 2 more answers

A perfectly straight 24 ft tall tree grows on the edge of the bank of a 45 foot wide river. A bird sitting at the top of the tre

True [87]

Answer:

Distance covered by the bird before meeting the water is: 51.264 ft

Step-by-step explanation:

Notice that if the bird catches the fish in 2 seconds, then the fish was able to dive down a total of 6 feet before being caught:

$distance=Vel\,* time=3\,\frac{ft}{s} *\,2\,\,s=6 \,\,ft$

So the bird needs to fly in the direction of the hypotenuse of a right angle triangle (see attached image) that has one leg of length (24 ft + 6 ft) = 30 ft, and another one 22.5 ft (half the width of the river.

Such hypotenuse is (using Pythagoras theorem):

$hyp =\sqrt{(60\,ft)^2+(22.5\.ft)^2} =\sqrt{4106.25} \,ft=64.08\,ft$

Now, in order to find the distance D the bird covers from the top of the tree to the water (marked in red in our image), we use similar triangles. The bigger triangle is that of legs 60 ft and 22.5 ft and hypotenuse 64.08 ft.

The smallest triangle we use in the proportion is the one shaded yellow in the image, which has one leg equal to 24 ft, and unknown hypotenuse:

So we make the proportion between known legs, and hypotenuses:

$\frac{24\,ft}{30\,ft} =\frac{D}{64.08\,ft} \\D=\frac{64.08\,ft\,*\,24\,ft}{30\,ft} \\D=51.264\,ft$