Can you help me solve this please?

Mathematics

2 answers:

Aleksandr [31]3 years ago

3 0

The answer is 840 180+180+180+180=720
720+60+60=840

Alina [70]3 years ago

3 0

I am not sure if this is correct but I got 696m cubed

You might be interested in

Adding two rational numbers if a pair of Addends has the opposite signs then the sun will have the sign of the addend with the w

Mazyrski [523]

Adding two rational numbers if a pair of Addends has the opposite signs then the sun will have the sign of the addend with the with the greater value among the two.

These examples can better illustrate this concept:
Example 1:
23 + (-3) = 20 (The greater among the two is positive and the result is also positive)

Example 2:
-23 + 3 = -20 (The greater among the two is negative and the result is also negative)

3 0

3 years ago

Solve each quadratic equation by completing the square. Give exact answers--no decimals.

Sholpan [36]

Answer:

$x_1 = -2 + 2i\\\\x_2 = -2 -2i$

Step-by-step explanation:

In this problem we have the equation of the following quadratic equation and we want to solve it using the method of square completion:

$7x ^ 2 + 28x +56 = 0$

The steps are shown below:

For any equation of the form: $ax ^ 2 + bx + c = 0$

1. If the coefficient a is different from 1, then take a as a common factor.

In this case $a = 7$ . Then:

$7(x ^ 2 + 4x) = -56$

2. Take the coefficient b that accompanies the variable x. In this case the coefficient is 4. Then, divide by 2 and the result squared it.

We have:

$\frac{4}{2} = 2\\\\(\frac{4}{2})^2 = 4$

3. Add the term obtained in the previous step on both sides of equality, remember to multiply by the common factor $a = 7$ :

$7(x ^ 2 + 4x + 4) = -56 + 7(4)$

4. Factor the resulting expression, and you will get:

$7(x + 2) ^ 2 = -28$

Now solve the equation:

Note that the term $7(x + 2) ^ 2$ is always $> 0$ therefore it can not be equal to -28.

The equation has no solution in real numbers.

In the same way we can find the complex roots:

$7(x+2)^2 = -28\\\\(x+2)^2 = -\frac{28}{7}\\\\x+2 = \sqrt{-\frac{28}{7}}\\\\x = -2 + \sqrt{-4}\\\\x = -2 + 2\sqrt{-1}\\\\x_1 = -2 + 2i\\\\x_2 = -2 -2i$