Let x be the length of one side of the smaller square Let y be the length of one side of the larger square 4x would be the perimeter of the smaller square, as it has 4 sides Therefore 4x = y + 10, as the perimeter of the smaller square is 10 inches bigger than one side of the larger square. We're going to solve this question using simultaneous equations. This means we need another equation to compare the first one to. Since we know that one side of the larger square is 2 inches bigger than the first one, we can make the equation y = x + 2 Know that we know the value of y in terms of x, we can introduce this value to the original equation to find: 4x = (x + 2) + 10 Therefore: 4x = x + 12 3x = 12 x = 4 Now that we know the size of the sides on the smaller square, we can figure out the size of the larger square by using our second equation (y = x + 2) y = 4 + 2 y = 6 Therefore, the length of each side of the larger square is<u> B.6</u>
So...the diameter is increasing at a rate if 2cm/minute, therefore the radius (1/2 the diameter) is increasing at half the rate. You will learn how to calculate the rate of change at a specific point in time in calculus.
