Please help me im stressing :((

Mathematics

1 answer:

Olegator [25]3 years ago

7 0

9514 1404 393

Answer:

wrong: -2x² -x² ⇒ -2x²
correct: x³ -3x² +6

Step-by-step explanation:

The point of these "what was done wrong" exercises is to see if you know what the correct steps look like.

On line 2, Danielle correctly distributed the minus sign to eliminate the second set of parentheses. (There is often a problem with minus signs and parentheses, so it is nice to see it done correctly.)

On line 3, the two x² terms are incorrectly combined. It looks as though Danielle simply dropped the -x² term because it disappeared without changing the coefficient of x² from -2x². The correct sum of those terms is ...

-2x² -x² = -3x²

so the correct work on line 3 is ...

x³ -3x² +6

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-12 = 4x + 1<br> solve<br> algebra

Eddi Din [679]

Answer:

$x=-\frac{13}{4}$

Step-by-step explanation:

$-12=4x+1\\4x=-12-1\\x=-\frac{13}{4}$

4 0

3 years ago

See the picture below

mart [117]

Answer:

a) 301.59 cubic centimeters

b) 235.87 square centimeters

Step-by-step explanation:

Volume of ice cream cone is volume of hemisphere PLUS volume of cone.

Volume of Hemisphere = $\frac{\frac{4}{3}\pi r^3}{2}$

radius is given as 4, so,

Volume of Hemisphere = $\frac{\frac{4}{3}\pi r^3}{2}\\=\frac{\frac{4}{3}\pi (4)^3}{2}\\=134.04$

Now, Volume of Cone = $\frac{1}{3}\pi r^2 h$

Where radius is 4 and height is 10, so,

Volume of Cone = $\frac{1}{3}\pi r^2 h\\=\frac{1}{3}\pi (4)^2 (10)\\=167.55$

Volume of Ice Cream Cone = 134.04 + 167.55 = 301.59 cubic centimeters

Surface area of ice cream cone is surface area of hemisphere PLUS surface area of cone.

Surface Area of Hemisphere = $2\pi r^2\\=2\pi (4)^2\\=100.53$

Surface Area of Cone = $\pi r^2+\pi rl$

We dont need to use the first part, $\pi r^2$ since it is "inside". We need to find l, slant height, by using pythagorean theorem on a triangle we can make (bottom right).