All Answers 358406 Answers

what is 1/8+7/12

Simplify the following:
1/8+7/12

Put 1/8+7/12 over the common denominator 24. 1/8+7/12  =  3/24+(2×7)/24:
3/24+(2×7)/24

2×7  =  14:
3/24+14/24

3/24+14/24  =  (3+14)/24:
(3+14)/24

3+14 = 17:
Answer: | 
| 17/24

Guten Abend Radix !

Den schönen Abend wünsche ich Dir auch!

Gruß heureka!

Given that sqrt40 = k sqrt10 Find the value of k and please explain

\(\begin{array}{rcll} \sqrt{40 } &=& k\cdot \sqrt{10} & \qquad |\qquad \text{square both sides} \\ (\sqrt{40 })^2 &=& (k\cdot \sqrt{10})^2 \\ 40 &=& k^2\cdot 10 & \qquad |\qquad :10 \\ \frac{40}{10} &=& k^2 & \\ 4 &=& k^2 & \\ k^2 &=& 4 &\qquad |\qquad \sqrt{()} \text{ both sides} \\ \sqrt{ k^2 } &=& \sqrt{4} & \\ \mathbf{k} & \mathbf{=} & \mathbf{2}& \\ \end{array}\)

Given that sqrt40 = k sqrt10 Find the value of k and please explain

k=sqrt(40)/sqrt(10, but 40=2 X 2 X 10=2sqrt(10), so we have:

k=2sqrt(10)/sqrt(10), sqrt(10) cancels out, so we have:

k=2

Bravo heureka!!. It was a trick question! You certainly know your Calendar rules. Congrats.

Solve for x: \(2x^2+3x-8=0\)

\(\begin{array}{rcl} \boxed{~ \begin{array}{rcl} ax^2+bx+c &=& 0\\ x &=& {-b \pm \sqrt{b^2-4ac} \over 2a}\\ \end{array} ~}\\ 2x^2+3x-8&=&0 \qquad a= 2 \quad b = 3 \quad c = -8\\ x &=& {-b \pm \sqrt{b^2-4ac} \over 2a}\\ x &=& {-3 \pm \sqrt{3^2-4\cdot 2 \cdot(-8)} \over 2\cdot 2}\\ x &=& {-3 \pm \sqrt{9+ 64} \over 4}\\ x &=& {-3 \pm \sqrt{73} \over 4}\\ \hline x_1 &=& {-3 + \sqrt{73} \over 4}\\ x_1 &=&1.3860009363\\ \hline x_2 &=& {-3 - \sqrt{73} \over 4}\\ x_2 &=& -2.8860009363 \end{array}\)

A more important question in the same vein is:

On what day of the week will February 29, 3000 AD, fall??

Sorry no leap day there: \(\frac{3000}{400} = 7.5\)

The year is divisible by 4, but it is also divisible by 100, unfortunately, not also by 400.

No February 29, 3000 AD.

Leap day, 29th February, in 2004 fell on a Sunday. On what day of the week will the leap day in 2012 fall?

a. Monday

b. Friday

c. Wednesday

d. Thursday 

29th February, in 2004 ( Sunday )  \(\rightarrow\) 29th February, in 2012 ( ? )

Difference 8 Years in Days:

\(= 6\cdot 365\ \text{days} + 2 \cdot 366\ \text{days}\\ = 2922\ \text{days}\)

In weeks:

\(\frac{2922\ \text{days} } {7} = 417\ \text{weeks} \text{ and }\mathbf{ 3\ \text{days} }\)

Sunday + 3 days = Wednesday

29th February, in 2004 ( Sunday )  \(\rightarrow\) 29th February, in 2012 ( Wednesday )

c. Wednesday

what is sin 0=0

The first answer here gives the penalty for the nth day.

The second answer gives the total cumulative penalty from day 1 to the nth day.

You are going to have to be more specific about what you mean by \(y=mx+b\)

What do you want to know?

THAT'S IS EASIEST QUESTION OF TODAY!!!!!!!.

FEBRURAY 29, 2012 WAS ON A "WEDNESDAY"!!!!.

What is the equation of the line that passes through the point (-2,10) and is parallel to the line y = -4x - 3?

\(\begin{array}{rcl} \boxed{~ \begin{array}{rcl} y &=& m\cdot x +b \\ \end{array} ~}\\ (1) & x_1 &=& -2 \\ & y_1 &=&10\\ \hline & y_1 &= &m \cdot x_1 + b\\ & 10 &= &m \cdot (-2) + b\\ \hline (2) & y &=& -4x-3\\ & \text{slope } m &=& -4 \qquad \text{parallel line}\\ &\mathbf{m} &\mathbf{=}& \mathbf{4}\\ \hline & 10 &= &(-4) \cdot (-2) + b\\ & 10 &= &8 + b\\ &2 &= & b\\ &\mathbf{b} &\mathbf{=}& \mathbf{2}\\ \hline \boxed{~ \begin{array}{rcl} y &=& m\cdot x +b \\ y &=& -4x + 2 \end{array} ~} \end{array}\)

Learn to use the calculator here. Just enter the first number, then click on / sign, enter the second number and press = key.

what is -2/3 as a decimal=-.666666666666667.............................etc.

2.7000000USD remove 40%

27,000,000 - (40% X 27,000,000)=$16,200,000

Simplify the following:
-2+(-(8 (-4))-10) (-3)

-8 (-4)  =  32:
-2+(32-10) (-3)

-10+32 = 22:
-2+22 (-3)

22 (-3)  =  -66:
-2+-66

-2-66 = -(2+66):
-(2+66)

2+66 = 68:
Answer: | 
| -68

(3! + 4)^2 X -1= -100

12 + 3/4=12.75

Thank you ! :D 

If you try to construct it you will understand why what CPhill is telling you is so.  

The 2 short sides will not be long enough to touch each other.

Oh dear, that would be a three intervals that can't 'hold hands'  not much of a tirangle I am afraid.    

Tues 3/11/15

1)  Practical linear functions.   Thanks CPhill

     These are good practice question for middle and upper high school students.

     http://web2.0calc.com/questions/plants-linear-function

     http://web2.0calc.com/questions/pollution-linear

2) Kinetic energy and force      Not answered yet.

     http://web2.0calc.com/questions/physics-help-please

3) Interesting inequality     Melody

    http://web2.0calc.com/questions/16-684-x-a#r1

4) Fun with indices        Melody

    http://web2.0calc.com/questions/exam-question-2-2015-5-2019#r1

5) Vectors      Thanks  CPhill

    http://web2.0calc.com/questions/vectors_50924

6) Physics      Not answered

   http://web2.0calc.com/questions/physics-problem-help