2 plus 2 is 4. However if you take away 1 it becomes 3.

The area of a sphere is actually a surface area as a sphere is a 3 dimensional object. The area of a sphere is equal to 4 x pi x the radius squared. It's derivation is very interesting and is done by using multi sided polygons inside the sphere, further individual research is recommended.

I would recommend the coloumn method of subtraction in this scenario. 867 - 146 --------- 721 Always line up your numbers with the correct place values underneath each other and begin your subtraction from the left.

This depends on each equation individually. The most general answer for this would be to perform inverse operations in the opposite of BIDMAS to the variable who's value you want to find.

To find an approximate value for the square root of a number N, you can find the closest square number smaller than N and the closest square number larger than N. The square roots of the square numbers will be easy to calculate and should be 1 apart. The square root of N will be some number between the square roots of each square. To find N by trial and error you could then just try different numb... more

The balance method is used to solve equations. If follows the principle of balancing both sides of an equation. To perform this method, whatever operation is done to one side of the equation needs to also be done to the other. This is continued until you have found a numerical value for the variable in question

Angles in any type of triangle always have a sum of 180 degrees. The proof of this includes a straight line and knowing how angles interact with parallel and perpendicular lines. I would recommend further investigation on youtube as it is much easier to understand it visually.

The square root is the inverse of the square function. It asks what number was multipled by itself to achieve in this case 144. By using our knowledge of the basic times table we can identify that it is 12.

Simply multiply 0.09 by $30 and it gives you $2.7 Which is your tax !

To calculate the percentage increase: First: work out the difference (increase) between the two numbers you are comparing. Increase = New Number - Original Number Then:  divide the increase by the original number and multiply the answer by 100. % increase = Increase ÷ Original Number × 100. If your answer is a negative number then this is a percentage decrease. To calculate percentage decrea... more