Mathematics
Grade-8
Easy
Question
Solve the following using the substitution method and find the value of x and y:
5x – 2y = -4
-5x + 4y = 8
- 0, 1
- 1, 0
- -1, 0
- 0, 2
Hint:
The substitution method is the algebraic method to solve simultaneous linear equations. , in this method, the value of one variable from one equation is substituted in the other equation. In this way, a pair of the linear equation gets transformed into one linear equation with only one variable, which can then easily be solved.
The correct answer is: 0, 2
In this method, the elimination of the variable can be performed by substituting the value of another variable in an equation. Hence, this method is called the elimination by substitution method.
5x – 2y = -4 and -5x + 4y = 8
Given:
5x – 2y = -4 … (1)
-5x + 4y = 8 …(2)
The equation (1) can be written as
y = … (3)
Now, in equation (2) eliminate the variable y by substituting the value of y in terms of x from equation (3).
Hence, equation (2) becomes
-5x +4() = 8
Now, apply the distributive property for the above equation,
-5x +8 +10x = 8
5x = 0
x = 0
Hence, the value of x is 0.
Now, substituting x= 0 in the equation (3), we get
y =
y = 2
Therefore, the value of y is 2.
Hence, the solution for the system of linear equations is:
x = 0 and y=2
To check whether the obtained solution is correct or not, substitute the values of x and y in any of the given equations.
Verification:
Use Equation (1) to verify the solution
5x – 2y = -4
Now, substitute x= 0 and y=2
5(0) - 2(2) = -4
0 - 4 = -4
-4 = -4
Here, L.H.S = R.H.S
Thus, the obtained solution is correct.
Now, substitute x= 0 and y=2
5(0) - 2(2) = -4
0 - 4 = -4
-4 = -4
Here, L.H.S = R.H.S
Thus, the obtained solution is correct.
Related Questions to study
Mathematics
Solve the following using the substitution method and find the value of x and y:
-x + 2y = 3
3y = -3
Solve the following using the substitution method and find the value of x and y:
-x + 2y = 3
3y = -3
MathematicsGrade-8
Mathematics
Solve the following using the substitution method and find the value of x and y:
-2x - 2y = -14
-5x – y = -23
Solve the following using the substitution method and find the value of x and y:
-2x - 2y = -14
-5x – y = -23
MathematicsGrade-8
Mathematics
Solve the following using the substitution method and find the value of x and y:
- x – 4y =16
- 5x - 5y = 5
Solve the following using the substitution method and find the value of x and y:
- x – 4y =16
- 5x - 5y = 5
MathematicsGrade-8
Mathematics
Solve the following using the substitution method and find the value of x and y:
-5x = 25
3x + 5y = -35
Solve the following using the substitution method and find the value of x and y:
-5x = 25
3x + 5y = -35
MathematicsGrade-8
Mathematics
Solve the following using the substitution method and find the value of x and y:
5x + y = -10
2x + 5y = 19
Solve the following using the substitution method and find the value of x and y:
5x + y = -10
2x + 5y = 19
MathematicsGrade-8
Mathematics
What is the value of m when 5m = 100?
What is the value of m when 5m = 100?
MathematicsGrade-8
Mathematics
What is the value of x in the equation ax + b = 0?
What is the value of x in the equation ax + b = 0?
MathematicsGrade-8
Mathematics
How many solutions to the given system
y = 5 x + 4 and y = 4 + 5 x
How many solutions to the given system
y = 5 x + 4 and y = 4 + 5 x
MathematicsGrade-8
Mathematics
If slops are different then what is the solution of system linear equations?
If slops are different then what is the solution of system linear equations?
MathematicsGrade-8
Mathematics
Solve the following pair of equations.
- 2 x + 3 y= 12 and 4 x + 3 y = - 6
Solve the following pair of equations.
- 2 x + 3 y= 12 and 4 x + 3 y = - 6
MathematicsGrade-8
Mathematics
Solve the following pair of equations.
-2 x – 3 y = - 12 and 4 x - 3 y = 6
Solve the following pair of equations.
-2 x – 3 y = - 12 and 4 x - 3 y = 6
MathematicsGrade-8
Mathematics
Solve the following pair of equations.
Solve the following pair of equations.
MathematicsGrade-8
Mathematics
Coach Jhon buys 20 bats and 5 balls for his team.
A ball costs x rupees and a bat costs y rupees. John spends a total of 400 rupees on these two items.
Express x in terms of y.
Coach Jhon buys 20 bats and 5 balls for his team.
A ball costs x rupees and a bat costs y rupees. John spends a total of 400 rupees on these two items.
Express x in terms of y.
MathematicsGrade-8
Mathematics
2x +y = 10 Complete the missing value in the solution to the equation. (……..,- 6 )
2x +y = 10 Complete the missing value in the solution to the equation. (……..,- 6 )
MathematicsGrade-8
Mathematics
James needs to solve the system of equations using elimination.
-3x + 5y = 15 and 2x – 5y = -15
What variable should James should solve first
James needs to solve the system of equations using elimination.
-3x + 5y = 15 and 2x – 5y = -15
What variable should James should solve first
MathematicsGrade-8