Mathematics
Grade6
Easy
Question
Find the following expression with the values of x = 1 and y = 2
5x – 4y + 5
- 2
- 5
- 4
- 10
Hint:
This is an algebraic expression. An algebraic expression consists of two components: a variable and a constant. A variable is a quantity that doesn’t have any fixed value. It takes value according to the conditions. It is denoted by the alphabet. A constant is a quantity with a fixed value. In this question, value is assigned to the variables. We have to perform the required operations and find the final value.
The correct answer is: 2
The given expression is 5x-4y+5.
There are two variables and three constants in the above expression. The variables are: ‘x’ and ‘y’. Values assigned to the variables are x = 1 and y = 2. We have to substitute these values and find the final value of the expression.
There are three terms in the above expression. The first and second term have minus sign in between them. The second and third term addition sign. We have to first substitute the value and perform the required operations.
To substitute the value, we have to replace x by 1 and y by 2. After substituting the value, we will get the following equation:
5x-4y+5 = 5(1)-4(2)+5
Now we have to first multiply 5 by 1. We have to multiply 4 by 2. On multiplication, we get
5x-4y+5 = 5-8+5
5x-4y+5 = 2
Therefore, the value of equation is 2
So option (a), which is ‘2’, is the right option.
We have to be careful about the operations because the variables. We have to follow proper order for performing the operations. The variables take different values under different conditions. So we have to careful while substituting the values. The main part of such type of questions is just replacing the variables by their value and performing the operation.
