Question

How do you solve $ \dfrac{1}{3}(d + 3) = 5 $ ?

Answer 1

Hint: Linear equations are equations of the first order. These equations are defined for lines in the coordinate system. An equation for a straight line is called a linear equation. The general representation of the straight-line equation is y=mx+b, where m is the slope of the line and b is the y-intercept.

Complete step by step solution:
 As given equation is;
  $ \dfrac{1}{3}(d + 3) = 5 $
Open the bracket;
  $ \dfrac{d}{3} + 1 = 5 $
We have to calculate the value of $ d $ .
We will go step by step as given below:
 $ \dfrac{d}{3} + 1 = 5 $
Subtract $ 1 $ from both sides of the equation. We get,
  $ \Rightarrow \left( {\dfrac{d}{3} + 1} \right) - 1 = 5 - 1 $
  $ \Rightarrow \dfrac{d}{3} = 5 - 1 $
  $ \Rightarrow \dfrac{d}{3} = 4 $
Multiply both sides by $ 3 $ . we get,
Or, $ \dfrac{d}{3} = 4 $
Or, $ \left( {\dfrac{d}{3}} \right)3 = 4 \times 3 $
Or, $ d = 4 \times 3 $
Or, $ d = 12 $
Hence, $ d = 12 $
So, the correct answer is “ $ d = 12 $ ”.

Note: Let’s check our solution is it right or wrong,
Equation is $ \dfrac{1}{3}(d + 3) = 5 $
Keep $ d = 12 $ We get,
  $ \dfrac{1}{3}(12 + 3) = 5 $
Or $ \dfrac{1}{3}(15) = 5 $
Or $ 5 = 5 $
Hence LHS=RHS
So, our solution is correct.