Answer:
Length = 15 inches
Step-by-step explanation:
Let L represent the Length, W, the width and A, the area of the rectangle
from the question;
L = x + 5 .....eq 1
W = 3 2/5
Changing the value of W into an improper fraction; W = 17/5
A = 51 inches
Area of a rectangle, A = Lenght x Width
A = L X W ....eq 2
slotting the values of A, L and W in eq 2
51 = (x + 5) X 17/5
51 = ( 17/5x ) + ( 17/5 X 5 )
51 = 17/5x + 17
51 = 17x + 85
5
Cross multiply
5 X 51 = (17x + 85)X 1
255 = 17x + 85
Subtracting 85 from both sides
255 - 85 = 17x + 85 - 85
170 = 17x
Dividing both sides by the coefficient of x which is 17
10 = x
Therefore, x = 10
Slotting in the value of x in eq 2
L = 10 + 5
L = 15 inches
Let's check our answer by slotting in the values of A, W and L in eq 1
51 = 15 X 17/5
51 = 3 X 17
51 = 51
Since both sides of the equation are equal, the value of L is correct
