Mathematics · Quantitative Aptitude
Linear Equations
196 Questions
Linear equations involve solving for unknown variables in single or multi variable systems. These questions test algebraic manipulation and logical consistency skills. They are a core component of quantitative aptitude and advanced mathematics tests.
Solving simultaneous equationsSingle variable equationsSystem consistency checksIndeterminate equationsMatrix form solutions
Linear Equations Questions
Solve the following system of equations:
2x + 3y = 7
4x - 2y = 10
-
(x, y) = (2, 1)
-
(x, y) = (1, 2)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can use the elimination method. Multiplying the first equation by 2 and the second equation by 3, we get:
4x + 6y = 14
12x - 6y = 30
Adding the two equations, we get:
16x = 44
Solving for x, we get x = 2. Substituting x = 2 back into either of the original equations, we can solve for y. Using the first equation, we get 2(2) + 3y = 7, which gives y = 1. Therefore, the solution is (x, y) = (2, 1).
Solve the following system of equations:
y = x^2 - 1
y = 2x - 3
-
(x, y) = (2, 1)
-
(x, y) = (1, 2)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can substitute the first equation into the second equation. Substituting y = x^2 - 1 into y = 2x - 3, we get x^2 - 1 = 2x - 3. Rearranging the equation, we get x^2 - 2x + 2 = 0. Factoring the quadratic equation, we get (x - 2)(x - 1) = 0. Setting each factor equal to zero, we get x = 2 and x = 1. Substituting x = 2 back into the first equation, we get y = 2^2 - 1 = 3. Therefore, the solution is (x, y) = (2, 1).
Solve the following system of equations:
3x + 2y = 5
2x - y = 1
-
(x, y) = (1, 2)
-
(x, y) = (2, 1)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can use the substitution method. Solving the second equation for y, we get y = 2x - 1. Substituting this into the first equation, we get 3x + 2(2x - 1) = 5. Solving for x, we get x = 1. Substituting x = 1 back into the second equation, we get y = 2(1) - 1 = 1. Therefore, the solution is (x, y) = (1, 2).
Solve the following system of equations:
2x + 3y = 7
4x - 2y = 10
-
(x, y) = (2, 1)
-
(x, y) = (1, 2)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can use the elimination method. Multiplying the first equation by 2 and the second equation by 3, we get:
4x + 6y = 14
12x - 6y = 30
Adding the two equations, we get:
16x = 44
Solving for x, we get x = 2. Substituting x = 2 back into either of the original equations, we can solve for y. Using the first equation, we get 2(2) + 3y = 7, which gives y = 1. Therefore, the solution is (x, y) = (2, 1).
Solve the following system of equations:
y = x^2 - 1
y = 2x - 3
-
(x, y) = (2, 1)
-
(x, y) = (1, 2)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can substitute the first equation into the second equation. Substituting y = x^2 - 1 into y = 2x - 3, we get x^2 - 1 = 2x - 3. Rearranging the equation, we get x^2 - 2x + 2 = 0. Factoring the quadratic equation, we get (x - 2)(x - 1) = 0. Setting each factor equal to zero, we get x = 2 and x = 1. Substituting x = 2 back into the first equation, we get y = 2^2 - 1 = 3. Therefore, the solution is (x, y) = (2, 1).
Solve the following system of equations:
3x + 2y = 5
2x - y = 1
-
(x, y) = (1, 2)
-
(x, y) = (2, 1)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can use the substitution method. Solving the second equation for y, we get y = 2x - 1. Substituting this into the first equation, we get 3x + 2(2x - 1) = 5. Solving for x, we get x = 1. Substituting x = 1 back into the second equation, we get y = 2(1) - 1 = 1. Therefore, the solution is (x, y) = (1, 2).
Solve the following system of equations:
2x + 3y = 7
4x - 2y = 10
-
(x, y) = (2, 1)
-
(x, y) = (1, 2)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can use the elimination method. Multiplying the first equation by 2 and the second equation by 3, we get:
4x + 6y = 14
12x - 6y = 30
Adding the two equations, we get:
16x = 44
Solving for x, we get x = 2. Substituting x = 2 back into either of the original equations, we can solve for y. Using the first equation, we get 2(2) + 3y = 7, which gives y = 1. Therefore, the solution is (x, y) = (2, 1).
Solve the following system of equations:
y = x^2 - 1
y = 2x - 3
-
(x, y) = (2, 1)
-
(x, y) = (1, 2)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can substitute the first equation into the second equation. Substituting y = x^2 - 1 into y = 2x - 3, we get x^2 - 1 = 2x - 3. Rearranging the equation, we get x^2 - 2x + 2 = 0. Factoring the quadratic equation, we get (x - 2)(x - 1) = 0. Setting each factor equal to zero, we get x = 2 and x = 1. Substituting x = 2 back into the first equation, we get y = 2^2 - 1 = 3. Therefore, the solution is (x, y) = (2, 1).
Solve the following system of equations:
3x + 2y = 5
2x - y = 1
-
(x, y) = (1, 2)
-
(x, y) = (2, 1)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can use the substitution method. Solving the second equation for y, we get y = 2x - 1. Substituting this into the first equation, we get 3x + 2(2x - 1) = 5. Solving for x, we get x = 1. Substituting x = 1 back into the second equation, we get y = 2(1) - 1 = 1. Therefore, the solution is (x, y) = (1, 2).
Solve the following system of equations:
2x + 3y = 7
4x - 2y = 10
-
(x, y) = (2, 1)
-
(x, y) = (1, 2)
-
(x, y) = (3, -1)
-
(x, y) = (-1, 3)
A
Correct answer
Explanation
To solve this system of equations, we can use the elimination method. Multiplying the first equation by 2 and the second equation by 3, we get:
4x + 6y = 14
12x - 6y = 30
Adding the two equations, we get:
16x = 44
Solving for x, we get x = 2. Substituting x = 2 back into either of the original equations, we can solve for y. Using the first equation, we get 2(2) + 3y = 7, which gives y = 1. Therefore, the solution is (x, y) = (2, 1).
Which of the following is an example of an indeterminate equation?
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$x + y = 5$
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$x^2 + y^2 = 1$
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$x^3 + y^3 = z^3$
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$x^2 - y^2 = 1$
D
Correct answer
Explanation
An indeterminate equation is one that has infinitely many solutions. $x^2 - y^2 = 1$ is an example of an indeterminate equation, as it has infinitely many integer solutions for $x$ and $y$.
What is the solution to the equation x^2 - 4x + 3 = 0?
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x = 1, x = 3
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x = 2, x = 4
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x = 3, x = 5
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x = 4, x = 6
A
Correct answer
Explanation
We can solve this equation using the quadratic formula: x = (-b ± √(b^2 - 4ac)) / 2a. Substituting a = 1, b = -4, and c = 3, we get x = (-(-4) ± √((-4)^2 - 4(1)(3))) / 2(1) = (4 ± √(16 - 12)) / 2 = (4 ± √4) / 2 = (4 ± 2) / 2. Therefore, the solutions are x = 1 and x = 3.
Solve the system of equations: (x + 2y = 5) and (2x - y = 1).
-
\((x, y) = (1, 2)\)
-
\((x, y) = (2, 1)\)
-
\((x, y) = (3, 0)\)
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\((x, y) = (0, 3)\)
A
Correct answer
Explanation
To solve the system of equations, we can use the substitution method. First, solve one of the equations for one of the variables. For example, we can solve the first equation for (x): (x = 5 - 2y). Then, substitute this expression for (x) into the other equation: (2(5 - 2y) - y = 1). This gives us (10 - 4y - y = 1), which simplifies to (-5y = -9). Dividing both sides by (-5), we get (y = 9/5). Substituting this value of (y) back into the first equation, we get (x + 2(9/5) = 5), which simplifies to (x = 1). Therefore, the solution to the system of equations is ((x, y) = (1, 2)).
Solve the system of equations: (3x + 2y = 7) and (2x - y = 1).
-
\((x, y) = (1, 2)\)
-
\((x, y) = (2, 3)\)
-
\((x, y) = (3, 4)\)
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\((x, y) = (4, 5)\)
B
Correct answer
Explanation
To solve the system of equations, we can use the elimination method. First, multiply the second equation by 2 to get (4x - 2y = 2). Then, add this equation to the first equation to get (7x = 9). Dividing both sides by 7, we get (x = 9/7). Substituting this value of (x) back into the first equation, we get (3(9/7) + 2y = 7), which simplifies to (y = 3). Therefore, the solution to the system of equations is ((x, y) = (2, 3)).
Solve the system of equations: (x + y = 5) and (x - y = 1).
-
\((x, y) = (2, 3)\)
-
\((x, y) = (3, 2)\)
-
\((x, y) = (4, 1)\)
-
\((x, y) = (1, 4)\)
B
Correct answer
Explanation
To solve the system of equations, we can use the addition method. First, add the two equations together to get (2x = 6). Dividing both sides by 2, we get (x = 3). Substituting this value of (x) back into the first equation, we get (3 + y = 5), which simplifies to (y = 2). Therefore, the solution to the system of equations is ((x, y) = (3, 2)).