Explanation: Convert to decimals: 0.5, 0.05, 5, 0.2. Order: 0.05, 0.2, 0.5, 5. So 0.05, 1/5, 1/2, 5. Option A has 0.5 before 0.05. Option B has 0.05 then 0.2 then 0.5 then 5, but written as 1/2,0.05,1/5,5 which is 0.5,0.05,0.2,5 €” not ordered. Option C has 0.05,0.5,0.2,5 €” not ordered.

Explanation: An equation is a statement that two expressions are equal, containing an equals sign. x=2 is an equation. x²+xy-y is an expression, not an equation. 3x-4=20y^2 is an equation. 13y=y+1 is an equation. x/5=9 is an equation. Therefore, the equations are A, C, D, and E.

Explanation: The expression has three terms: 5x², 2x, and -2. The term -2 is a constant. Option A is incorrect because there are three terms and one is a constant. Option B is wrong as there are three terms. Option D is incorrect because not all terms are constants; 5x² and 2x are variable terms.

Explanation: Coefficients are the numerical factors of the terms. For 12x³, the coefficient is 12; for 7x², it is 7; for 24x, it is 24. So the coefficients are 12, 7, and 24. Option A lists digits from the exponents. Option B misses 24. Option D includes digits that are not coefficients.

Explanation: To find the sum of the lengths of the sides of the polygon, we first identify the given side lengths: AB = 10- 2x, BC = x+3, CD=4x-5, DE = 6x-7, EF = 62-5, and FA = 42 +2. Next, we add these expressions together: (10-2)+(x+3)+(4x-5)+(6x-7)+(6x-5)+(4x+2). Combining like terms, we group all coefficients of a and constant values: (-2x+x+4x+6x+6x+ 4x)+(10+3-5-7-5+2). Simplifying further, the coefficient of adds up to 192, while the constants simplify to -2. Therefore, the total sum of the lengths of all the sides of the polygon is 19 - 2. This expression represents the perimeter of the polygon in terms of 2.