Question

If a=2 and b=3, find the value of \[2a - 3b\]?

Answer 1

Hint: Here in this question, we have to find the value of a given algebraic expression by using a given value of variables. To find this we have to substitute the a and b values in the given algebraic expression and by further simplification using a basic arithmetic operation to get the required solution.

Complete step-by-step answer:
Algebraic expression is a mathematical term that consists of variables and constants along with mathematical operators (subtraction, addition, multiplication, etc).
consider the given algebraic expression:
\[ \Rightarrow \,\,2a - 3b\]
Which is an expression with two terms is known as binomial.
Here ‘a’ and ‘b’ are the variables whose value is unknown, it can vary depending upon situations and 2 and 3 are coefficients of the variables that will remain unchanged.
From the question
We know that a=2. Substitute the value of “a” in the given equation:
\[ \Rightarrow \,\,2\left( 2 \right) - 3b\]
On multiplying, we have
\[ \Rightarrow \,\,4 - 3b\]
Similarly, we know that b=3, Then substitute the value of "b" in the previous equation:
\[ \Rightarrow \,\,4 - 3\left( 3 \right)\]
Again, on multiplication, we have
\[ \Rightarrow \,\,4 - 9\]
On subtracting, we get
\[ \Rightarrow \,\, - 5\]
Hence, the value of \[2a - 3b = - 5\] at a=2 and b=3.
So, the correct answer is “-5”.

Note: The value of algebraic expression will vary as the value of a variable varies. A variable is a letter whose value is unknown, it can take any value depending upon the situation. If the variable value is integer, then we should take care of the sign of the algebraic expression using a sign convention and simplify algebraic expression using mathematical operations.