Question

In the aigebrait equation 9n -5-85. n is the variable while 5 and 85 are constants. What is a variable? A A variable has a fixed value that does not change. B. Avariable is an expression that combines numbers C. A vanable is any letter or symbol that represents a number. D. Avariable is a mathematical phrase 30. A car truvels at a speed of 75 kilometers per hour. Express its speed in algebraic equation ifit slews down by 20 kilometers per hour.

A 75x 20 N
B 75 20 N
C 75+ 20 N
D. 75-20-N 31.

Answer 1

A variable is a symbol representing a number that can vary, as seen in '9n - 5 = 85' where 'n' is the variable. The new speed of the car slowing down from 75 km/h by 20 km/h is represented by the algebraic expression '75 - 20'.

Step-by-step explanation:

In the algebraic equation 9n - 5 = 85, the term n is considered a variable. A variable is a symbol, often a letter, that represents a number which can change or vary within the context of a mathematical problem. We can see that the correct answer to the question 'What is a variable?' is option C: A variable is any letter or symbol that represents a number.

Regarding the second question, if a car travels at a speed of 75 kilometers per hour and it slows down by 20 kilometers per hour, the algebraic expression to represent its new speed would be 75 - 20. Answer D is correct. It's important to note that we do not include the variable 'N' in this expression, as the question requires a simple numerical expression, not a variable-inclusive equation.