Question

How do you solve $3x + 5 = 20$ ?

Answer 1

Hint: For this type of question we should follow the BODMAS rule. Solve for x by sending x terms to one side and constant terms to one side. We can check for the answer whether the answer is correct or not by substituting the answer in the place of x.

Step by step solution:
The objective of the problem is to solve $3x + 5 = 20$
Given equality $3x + 5 = 20$
To solve the above equality we should follow the BODMAS rule.
About the BODMAS rule: this rule explains the order of the operations that to be performed first. In BODMAS B stands for “brackets'', O stands for “order of “, M stands for “multiplication”, A stands for ”addition” and S stands for “ subtraction”. We should follow this rule to eradicate the wrong answers while simplifying or solving the equations.
To solve the given equation $3x + 5 = 20$
First, let us take 5 to the right side. while sending any number either to the right or left that changes its original sign that is if there is a positive sign it changes to negative and if there is a negative sign it changes to positive.
That is subtracted 5 on both sides, we get
$ \Rightarrow 3x + 5 - 5 = 20 - 5$
On solving the above equation we get
$ \Rightarrow 3x = 15$
Dividing with 3 into both sides, we get
$ \Rightarrow \dfrac{{3x}}{3} = \dfrac{{15}}{3}$
On solving the above equation we get
$ \Rightarrow x = 5$
Thus, the value of x is 5.
Verification: we can verify answers by substituting the value of x in the given equation. After substituting if the left-hand side term(LHS) is equal to the right-hand side term(RHS) then the answer we get is correct otherwise not.
Now substitute in 5 in the place of x in $3x + 5 = 20$, we get
$
   \Rightarrow 3\left( 5 \right) + 5 = 20 \\
   \Rightarrow 20 = 20 \\
 $
Therefore , LHS =RHS

Thus our answer 5 is correct.

Note :
On solving these types of questions one should be careful about the signs that are plus and minus. In multiplication, if both signs are equal then the resultant sign will be positive and if both the signs are different then the resultant sign will be negative.