Original price of the second dress: a÷( 1-25%)=a÷0.75 (also in the form of fraction).
1. A store sells two clothes at a certain time at the price of one yuan each, one of which makes a profit of 25% and the other loses 25%.
The original price of these two clothes is expressed by algebraic expressions respectively.
Suppose the purchase price of the dress with a profit of 25% is X yuan, and the purchase price of the other dress is Y yuan.
According to the meaning of the question, x+0.25x=60.
X = 48 y-0.25 y = 60。
The solution is y = 80 60+60-48-80 =-8 (yuan)
Answer: 8 yuan to sell these two clothes is a loss.
2. Algebraic expressions are formulas obtained by algebraic operations such as addition, subtraction, multiplication, division, multiplication and root of finite numbers, or mathematical expressions containing letters are called algebraic expressions. For example: ax+2b, -2/3, b 2/26, √a+√2, etc.
3. Note:
1), excluding equal sign (=, ≦), unequal sign (≦, ≤, ≥,) and approximate equal sign.
2) There can be absolute values. For example: |x|, |-2.25| and so on.
1. The algebraic expression of a monomial without addition and subtraction is called a monomial. Single factor: the numerical factor in a single item is called the numerical factor (or letter factor) of a single item, or coefficient for short.
Number of times of a monomial: The sum of the indices of all the letters in the monomial is called the number of times of the monomial.
2. Polynomial The algebraic sum of several monomials is called polynomial; Each monomial in a polynomial is called a polynomial term. Items without letters are called constant items.
Polynomial Degree: In a polynomial, the degree of the term with the highest degree is the degree of the polynomial.
1) Homogeneous polynomial: Polynomials with the same degree are called homogeneous polynomials.
2) Irreducible Polynomial: A rational coefficient polynomial with a degree greater than zero is called an irreducible polynomial within the rational number range when it cannot be decomposed into the product of two rational coefficient polynomials with a degree greater than zero. Irreducible polynomials in the range of real numbers are one or several quadratic polynomials, and the complex norm is the same as that of internal irreducible polynomials.
3) Symmetric Polynomial: In a multivariate polynomial, if the result obtained by exchanging any two elements is the same as the original formula, it is said that this polynomial is a symmetric polynomial about these elements.
4) Similar terms: terms with the same letters and the same index of the same letters in polynomials are called similar terms.