The length of a rectangle is three centimeters more than twice the width. the perimeter is 78 centimeters. define a variable and write and solve an equation to find out how long and wide the rectangle is?

The rectangle is 27 centimetres long  and  12 centimetres wide.

Step-by-step explanation:

To solve this problem, we need to follow the steps below;

First, we need to write down the question in a mathematical form.

Let l equal to the length of the rectangle and w equal to the width of the rectangle;

From the question; "The length of a rectangle is three centimetres more than twice the width" can be written down mathematically as

l = 3 + 2w  ----------------------------------------------(1)

The question state that the perimeter is 78 centimetres.

Now the formula for calculating the perimeter of a rectangle is

perimeter = 2l + 2w

If the perimeter is 78 centimetres, this implies that;

2l + 2w = 78 ----------------------------------------------(2)

Equation (1) can be rearranged as;

l  - 2w = 3 ---------------------------------------------------(3)

We can now solve equation (2) and (3) simultaneously

Add equation (2) and equation (3) together

3l = 81

Divide both-side of the equation by 3

=

l = 27  

substitute l=27 into equation(1)

l = 3 + 2w

27 = 3 + 2w

subtract 3 from both-side of the equation

27 - 3 = 3-3 + 2w

24 = 2w

Divide both-side of the equation by 2

=

12 = w

w= 12

Therefore, the rectangle is 27 centimetres long  and  12 centimetres wide.

2.

according to newton’s cannonball model, what happens if the cannonball's velocity is enough to overpower the pull of earth’s gravitystep-by-step explanation:

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step-by-step explanation: