Written Instructions:
For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..
For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.
Leave your answers in the simplest form or correct to two decimal places.
1) Solve the following systems of equations using cross multipilication method. 0.5x + 0.8y = 0.44 ; 0.8x + 0.6y = 0.5 X = Y = Answer:_______________ |
2) Solve the following systems of equations using cross multipilication method. 9x + 12y = 72 , 60x - 33y = 141 X = Y = Answer:_______________ |
3) Solve the following systems of equations using cross multipilication method. - = 2 ; + = X = Y = Answer:_______________ |
4) Solve the following systems of equations using cross multipilication method. 1x + 1.6y = 0.88 ; 1.6x + 1.2y = 1 X = Y = Answer:_______________ |
5) Solve the following systems of equations using cross multipilication method. 3x + 4y = 24 , 20x - 11y = 47 X = Y = Answer:_______________ |
6) Solve the following systems of equations using cross multipilication method. - = 6 ; + = X = Y = Answer:_______________ |
7) Solve the following systems of equations using cross multipilication method. 1.5x + 2.4y = 1.32 ; 2.4x + 1.8y = 1.5 X = Y = Answer:_______________ |
8) Solve the following systems of equations using cross multipilication method. 6x + 8y = 48 , 40x - 22y = 94 X = Y = Answer:_______________ |
9) Solve the following systems of equations using cross multipilication method. - = 4 ; + = X = Y = Answer:_______________ |
10) Solve the following systems of equations using cross multipilication method. 0.5x + 0.8y = 0.44 ; 0.8x + 0.6y = 0.5 X = Y = Answer:_______________ |
1) Solve the following systems of equations using cross multipilication method. 0.5x + 0.8y = 0.44 ; 0.8x + 0.6y = 0.5 X = Answer: 0.4 Y = Answer: 0.3 SOLUTION 1 : solution: 0.5x + 0.8y - 0.44 = 0 ........(1) 0.8x + 0.6y - 0.5 = 0 .........(2) Here , a1 = 0.5, b1 = 0.8, c1 = - 0.44 a2 = 0.8, b2 = 0.6, c2 = - 0.5 a1b2 - a2b1 = 0.5(0.6) - 0.8 x 0.8 = - 0.3 - 0.64 = -0.34 ≈ 0. Thus, the system has a unique solutions. Consider,
We have 0.8 x 0.5 = -0.4 , 0.6 x -0.44 = 0.264, -0.44 x 0.8 = -0.352, -0.5 x 0.5 = -0.25 0.5 x 0.6 = -0.3, 0.8 x 0.8 = 0.64
⇒
⇒
⇒
x = 0.4
⇒
y = 0.3 Hence the solution is ( 0.4, 0.3 ).
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2) Solve the following systems of equations using cross multipilication method. 9x + 12y = 72 , 60x - 33y = 141 X = Answer: 4 Y = Answer: 3 SOLUTION 1 : solution: 9x + 12y - 72 = 0 ........(1) 60x - 33y - 141 = 0 .........(2) Here , a1 = 9, b1 = 12, c1 = - 72 a2 = 60, b2 = 33, c2 = - 141 a1b2 - a2b1 = 9(-33) - 60 x 12 = - 297 - 720 = -1017 ≈ 0. Thus, the system has a unique solutions. Consider,
We have 12 x -141 = -1692 , -33 x -72 = 2376, -72 x 60 = -4320, -141 x 9 = -1269 9 x -33 = -297, 60 x 12 = 720
⇒
⇒
⇒
x = 4
⇒
y = 3 Hence the solution is ( 4, 3 ).
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3) Solve the following systems of equations using cross multipilication method. - = 2 ; + = X = Answer: 2 Y = Answer: 3 SOLUTION 1 : solution: - = -2
9x - 10y = -12
9x - 10y + 12 = 0 ........(1)
+ =
3x + 2y - 13 = 0 .........(2) Here , a1 = 9, b1 = -10, c1 = 12 a2 = 2, b2 = 3, c2 = - 13 a1b2 - a2b1 = (9x3) - (2 x 10) = 27 + 20 = 47 ≈ 0. Thus, the system has a unique solutions. Consider,
We have -10 x -13 = 130 , 3 x 12 = 36, 12 x 2 = 24, 13 x 9 = 117 9 x 3 = 27, 2 x 10 = 20
⇒
⇒
⇒
x = 2
⇒
y = 3 Hence the solution is ( 2, 3 ).
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4) Solve the following systems of equations using cross multipilication method. 1x + 1.6y = 0.88 ; 1.6x + 1.2y = 1 X = Answer: 0.4 Y = Answer: 0.3 SOLUTION 1 : solution: 1x + 1.6y - 0.88 = 0 ........(1) 1.6x + 1.2y - 1 = 0 .........(2) Here , a1 = 1, b1 = 1.6, c1 = - 0.88 a2 = 1.6, b2 = 1.2, c2 = - 1 a1b2 - a2b1 = 1(1.2) - 1.6 x 1.6 = - 1.2 - 2.56 = -1.36 ≈ 0. Thus, the system has a unique solutions. Consider,
We have 1.6 x 1 = -1.6 , 1.2 x -0.88 = 1.056, -0.88 x 1.6 = -1.408, -1 x 1 = -1 1 x 1.2 = -1.2, 1.6 x 1.6 = 2.56
⇒
⇒
⇒
x = 0.4
⇒
y = 0.3 Hence the solution is ( 0.4, 0.3 ).
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5) Solve the following systems of equations using cross multipilication method. 3x + 4y = 24 , 20x - 11y = 47 X = Answer: 4 Y = Answer: 3 SOLUTION 1 : solution: 3x + 4y - 24 = 0 ........(1) 20x - 11y - 47 = 0 .........(2) Here , a1 = 3, b1 = 4, c1 = - 24 a2 = 20, b2 = 11, c2 = - 47 a1b2 - a2b1 = 3(-11) - 20 x 4 = - 33 - 80 = -113 ≈ 0. Thus, the system has a unique solutions. Consider,
We have 4 x -47 = -188 , -11 x -24 = 264, -24 x 20 = -480, -47 x 3 = -141 3 x -11 = -33, 20 x 4 = 80
⇒
⇒
⇒
x = 4
⇒
y = 3 Hence the solution is ( 4, 3 ).
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6) Solve the following systems of equations using cross multipilication method. - = 6 ; + = X = Answer: 2 Y = Answer: 3 SOLUTION 1 : solution: - = -6
81x - 90y = -108
81x - 90y + 108 = 0 ........(1)
+ =
9x + 6y - 39 = 0 .........(2) Here , a1 = 81, b1 = -90, c1 = 108 a2 = 6, b2 = 9, c2 = - 39 a1b2 - a2b1 = (81x9) - (6 x 90) = 729 + 540 = 1269 ≈ 0. Thus, the system has a unique solutions. Consider,
We have -90 x -39 = 3510 , 9 x 108 = 972, 108 x 6 = 648, 39 x 81 = 3159 81 x 9 = 729, 6 x 90 = 540
⇒
⇒
⇒
x = 2
⇒
y = 3 Hence the solution is ( 2, 3 ).
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7) Solve the following systems of equations using cross multipilication method. 1.5x + 2.4y = 1.32 ; 2.4x + 1.8y = 1.5 X = Answer: 0.4 Y = Answer: 0.3 SOLUTION 1 : solution: 1.5x + 2.4y - 1.32 = 0 ........(1) 2.4x + 1.8y - 1.5 = 0 .........(2) Here , a1 = 1.5, b1 = 2.4, c1 = - 1.32 a2 = 2.4, b2 = 1.8, c2 = - 1.5 a1b2 - a2b1 = 1.5(1.8) - 2.4 x 2.4 = - 2.7 - 5.76 = -3.06 ≈ 0. Thus, the system has a unique solutions. Consider,
We have 2.4 x 1.5 = -3.6 , 1.8 x -1.32 = 2.376, -1.32 x 2.4 = -3.168, -1.5 x 1.5 = -2.25 1.5 x 1.8 = -2.7, 2.4 x 2.4 = 5.76
⇒
⇒
⇒
x = 0.4
⇒
y = 0.3 Hence the solution is ( 0.4, 0.3 ).
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8) Solve the following systems of equations using cross multipilication method. 6x + 8y = 48 , 40x - 22y = 94 X = Answer: 4 Y = Answer: 3 SOLUTION 1 : solution: 6x + 8y - 48 = 0 ........(1) 40x - 22y - 94 = 0 .........(2) Here , a1 = 6, b1 = 8, c1 = - 48 a2 = 40, b2 = 22, c2 = - 94 a1b2 - a2b1 = 6(-22) - 40 x 8 = - 132 - 320 = -452 ≈ 0. Thus, the system has a unique solutions. Consider,
We have 8 x -94 = -752 , -22 x -48 = 1056, -48 x 40 = -1920, -94 x 6 = -564 6 x -22 = -132, 40 x 8 = 320
⇒
⇒
⇒
x = 4
⇒
y = 3 Hence the solution is ( 4, 3 ).
|
9) Solve the following systems of equations using cross multipilication method. - = 4 ; + = X = Answer: 2 Y = Answer: 3 SOLUTION 1 : solution: - = -4
36x - 40y = -48
36x - 40y + 48 = 0 ........(1)
+ =
6x + 4y - 26 = 0 .........(2) Here , a1 = 36, b1 = -40, c1 = 48 a2 = 4, b2 = 6, c2 = - 26 a1b2 - a2b1 = (36x6) - (4 x 40) = 216 + 160 = 376 ≈ 0. Thus, the system has a unique solutions. Consider,
We have -40 x -26 = 1040 , 6 x 48 = 288, 48 x 4 = 192, 26 x 36 = 936 36 x 6 = 216, 4 x 40 = 160
⇒
⇒
⇒
x = 2
⇒
y = 3 Hence the solution is ( 2, 3 ).
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10) Solve the following systems of equations using cross multipilication method. 0.5x + 0.8y = 0.44 ; 0.8x + 0.6y = 0.5 X = Answer: 0.4 Y = Answer: 0.3 SOLUTION 1 : solution: 0.5x + 0.8y - 0.44 = 0 ........(1) 0.8x + 0.6y - 0.5 = 0 .........(2) Here , a1 = 0.5, b1 = 0.8, c1 = - 0.44 a2 = 0.8, b2 = 0.6, c2 = - 0.5 a1b2 - a2b1 = 0.5(0.6) - 0.8 x 0.8 = - 0.3 - 0.64 = -0.34 ≈ 0. Thus, the system has a unique solutions. Consider,
We have 0.8 x 0.5 = -0.4 , 0.6 x -0.44 = 0.264, -0.44 x 0.8 = -0.352, -0.5 x 0.5 = -0.25 0.5 x 0.6 = -0.3, 0.8 x 0.8 = 0.64
⇒
⇒
⇒
x = 0.4
⇒
y = 0.3 Hence the solution is ( 0.4, 0.3 ).
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