Question

If y – x = 2 and the value of x is equal to 3 then find the value of y.

Answer 1

Hint: The given equation is a linear equation in two variables. Rewrite the given equation and convert it in the form of y = f(x), that is one unknown variable on the left hand side and the other variable on other sides and then put x = 3 in the equation to get the final answer.

Complete step by step answer:
To find the value of ‘y’ we will first write the given data, therefore
y – x = 2 ……………………………………………….. (1)
x = 3 ………………………………………………… (2)
If we shift ‘x’ to the right hand side of the equation (1) we will get,
Therefore, y = x + 2
To get the value of y we will substitute the value of equation (2) i.e. x = 3 in the above equation, therefore we will get,
Therefore, y = 3 + 2
If we add 3 and 2 in the above equation we will get,
Therefore, y = 5
Therefore, in equation y – x = 2, if x is equal to 3 then the value of y is equal to 5.

Note: Do remember that when ‘-x’ is shifted on the right hand side then its sign changes and becomes positive i.e. ‘+x’. Students sometimes in hurry forget to change the sign and obtain a wrong answer. We know that for finding the value of n variables there are required n equations. If we see here the value of x is given, we have only “y” as an unknown variable. So, we can find the value of y by directly putting the value of x.