4) The length of a rectangle is 2 cm less than 7 times

the width. The perimeter is 60 cm. Find the width and

length.

Answer : The width and  length of rectangle is, 4 cm and 26 cm respectively.

Explanation :

Let the length of rectangle be, 'x' and width of rectangle be, 'y'.

The length of a rectangle is 2 cm less than 7 times  the width. The equation will be:

           .............(1)

The perimeter of rectangle is 60 cm. The equation will be:

           .............(2)

Now put the value of 'x' from equation 1 to 2, we get:

Now put the value 'y' in equation 1, we get:

Thus, the width and  length of rectangle is, 4 cm and 26 cm respectively.

mechanics (greek   is that area of science concerned with the behaviour of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment. the scientific discipline has its origins in ancient greece with the writings of aristotle and archimedes[1][2][3] (see history of classical mechanics and timeline of classical mechanics). during the early modern period, scientists such as galileo, kepler, and newton laid the foundation for what is now known as classical mechanics. it is a branch of classical physics that deals with particles that are either at rest or are moving with velocities significantly less than the speed of light. it can also be defined as a branch of science which deals with the motion of and forces on objects. the field is yet less widely understood in terms of quantum theory.

explanation:

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.