Hi can anybody help please

Isaac wants the equation below to have no solution when the missing number is placed in the box. which number should he place in the box?

Which of the following domains provide a real value periods

An architect builds a model of a park in the shape of a rectangle. the model is 40.64 centimeters long and 66.04 centimeters wide. one inch equals 2.54 centimeters. use the ratio table to find the ratio of the length to the sum of the length and width in inches and in simplest form. length 40.64 width 66.04 a. 8: 21 b. 13: 21 c. 21: 13 d. 21: 8