Question

Find the value of y in the equation $2x + y = 7$, if x=$2$.

Answer 1

Hint: The value of x is given in the question. Substituting the value of x in the given equation we can find the value of y by interchanging the terms on other sides. And again, substituting the answer in our equation and finding the value is equal to \[7\] check the answer is correct.

Complete step by step answer:
Given that the equation is $2x + y = 7$ and also given that the value of x is$2$ .
Substitute the value of x = $2$ in the above equation we get
$2\left( 2 \right) + y = 7$
$4 + y = 7$
Now taking 4 to the other side of the equation, we get
$y = - 4 + 7$
$y = 3$
Therefore, the value of y is $3$.
To check whether the answer is correct or not, we can check it by substituting the value of y which we found in the above solution, if the answer is equal to $7$then the value of y is correct. If not, then the answer is incorrect. Substituting the found value of the variables x and y in the equation,
$2(2) + 3 = 7$
Therefore the value which we have found is correct.

Note: If the value of x is not given and the value of y=$3$ is given, then by following the same method (i.e.,) The value of y is given here. Substituting the value of x in the given equation we can find the value of x by interchanging the terms on other sides.
If two equations are given in the question without giving the values of x and y, we can find the values of x and y by using the elimination method. If any one value is given then we can find the other value directly by substituting them.