Question

Evaluate the expression x = 15 (Lesson 1.1).

200 – x

Short answer

The value of the expression is 185.

Step-by-step solution

– Explanation of Subtraction in mathematics

Subtraction is the process of taking away a number from another. It is a primary arithmetic operation that is denoted by a subtraction symbol (–) and is the method of calculating the difference between two numbers.

Example of subtraction

An example of subtraction is: 28 – 5 = 23.

Example: If a = 17 and b = 8, find the value of a – b

To evaluate the expressiona – b, substitute the value of a as 17 and the value of b as 8 and add the numbers as shown below,

$a-b = 17-8=9$

Evaluate the expression x + 4 when x = 15 

To evaluate the expression(200 – x), substitute the value of x as 15 and subtract 15 from 200, the result as shown below,

When x = 15 and the expression 200 – x

$\begin{array}{l}200-x\\ 200-15=185\end{array}$

Thus, the value of the expression is185.