Ключевые слова: accounting, add, addition, algebra, arithmetic, art, background, black, business, button, calculate, calculation, calculator, concept, design, divide, division, education, electronic, element, equal, financial, flat, formula, graphic, icon, isolated, math, mathematical, mathematics, maths, minus, multiplication, multiply, object, office, operation, plus, school, set, shape, sign, square, study, subtract, subtraction, symbol, technology, web, white,