Question

Solve $2x + 5 = 9$

Answer 1

Hint: Here we are asked to solve the given linear algebraic equation. The linear algebraic equation can be solved by three methods one of the effective methods is the transposition method. Here we will use the transposition method to solve the given equation. In the transposition method we will transfer the terms other than the unknown variable to the other side by doing that the operation on the transferring terms will get changed, that is addition will become subtraction and vice-verse and multiplication will become division and vice-versa. Then we will simplify the transferred terms to find the value of the unknown variable.

Complete step by step solution:
Given that $2x + 5 = 9$, and then we need to find the value of the unknown variable $x$, we will make use of the basic mathematical operations to simplify further. Now Turing the variables on the left-hand side and also the numbers on the right-hand side we get $2x + 5 = 9 \Rightarrow 2x = 9 - 5$ while changing the values on the equals to, the sign of the values or the numbers will change.
Or we can also able to apply the subtraction operation, subtract the number $5$ on both sides then we get $2x + 5 - 5 = 9 - 5$ equal values with opposite sign cancel each other, hence we get $2x = 9 - 5$
Again, using the subtraction, we get $2x = 4$
Now using the division operation, we have $x = \dfrac{4}{2} = 2$
Hence, we get the unknown value of the given variable as $x = 2$ .

Note: One of the other methods to solve the linear equation is trial and error. In this method we will substitute values for the unknown variable from $0,1,2,3,...$ so that the given equation will get satisfied. But using of this method will not be encouraged since it takes more time and also in linear equation there may be a chance that the unknown variable can have negative values so we also have to check it for negative values from $ - 1, - 2, - 3,...$ that is why we have used transposition method.