You just multipy the length (no matter what it is) by the width (no matter what that is). So... L x W = A Where L is Length, W is Width and A is Area. For your question about the area of a rectangle where the length is twice the width but no numbers are given then I guess a formula could be W x 2W = A. Or send me the exact question and I'll see if I can think of a better answer.
You times length by width
Do you know how to find the area of a circle when you know the radius ? Good! Do that. Do you know how to find the area of a square when you know the length of the side ? Good! Do that. Now you have two numbers ... the area of the circle and the area of the square. The problem wants you to find the difference of these two numbers. Do you know how to use subtraction to find the difference of two numbers ? Good! Do that.
If you are referring to a cube with 15mm sides then this is how you would work it out. A cube has 12 edges of the same length, and 6 faces of the same area. We know area is length^2 (length to the power of 2 / length X length. What you have to find is the total surface areo of all of the faces. If you can work out the area of one face you will know the area of the others. Since the area of one face is the area of one square, we can use the fomula length^2 which is also known as length X length. we also know in this instance the length of the square is 15mm. so we substitute 15 into the formula length X length: 15 X 15 =225 Square mm (we write square millimetres as we are refering to area [2 dimensions] But we have so far only worked out the area of one face. since there are 6 faces on a cube we multiply the area of one face by 6. So in this Case: 225 square mm X 6 =1350 square mm that is how you find the surface area of any cube.
That is the definition of the area of a rectangle. It does not work for any other shape.
You will have to work the surface area of one of the ends and then multiply that with the length.
length*width = 2*width*width i.e square the width and multiply by 2
Subtract twice the width from the perimeter. The answer will be twice the length. Divide by two.
Knowing just the length of the base you can not work out the area. You need the height and the base or the length of the hypotenuse in order to work out the area.
The length and width of a square are equal. Thus, find the square root of the area and the answer = length= width.
If you pretend that the width is X .Then you'll know that X times length = area. So if you say the length is 5 ,then the area is 10 the X must be 2 so the width is 2you simply work out what times the length makes the area.
You times length by width
Do you know how to find the area of a circle when you know the radius ? Good! Do that. Do you know how to find the area of a square when you know the length of the side ? Good! Do that. Now you have two numbers ... the area of the circle and the area of the square. The problem wants you to find the difference of these two numbers. Do you know how to use subtraction to find the difference of two numbers ? Good! Do that.
If you are referring to a cube with 15mm sides then this is how you would work it out. A cube has 12 edges of the same length, and 6 faces of the same area. We know area is length^2 (length to the power of 2 / length X length. What you have to find is the total surface areo of all of the faces. If you can work out the area of one face you will know the area of the others. Since the area of one face is the area of one square, we can use the fomula length^2 which is also known as length X length. we also know in this instance the length of the square is 15mm. so we substitute 15 into the formula length X length: 15 X 15 =225 Square mm (we write square millimetres as we are refering to area [2 dimensions] But we have so far only worked out the area of one face. since there are 6 faces on a cube we multiply the area of one face by 6. So in this Case: 225 square mm X 6 =1350 square mm that is how you find the surface area of any cube.
That is the definition of the area of a rectangle. It does not work for any other shape.
Work out each figure separately then add them together: Area of a trapezoid = 0.5*(sum of parallel bases)*height Area of a rectangle = length*height
Length x width
You will have to work the surface area of one of the ends and then multiply that with the length.