10 questions · Form 5 Mathematics Bab 2: Matrices
If [x + 2 5] = [7 y - 1], find the values of x and y.
Prefer reading to quizzing? All 10 questions are listed below with the answer and explanation under each one.
1. If [x + 2 5] = [7 y - 1], find the values of x and y.
Answer: A
Equating corresponding elements: x + 2 = 7 => x = 5; y - 1 = 5 => y = 6.
2. If matrix X + [[3, 4], [-1, 2]] = [[5, 1], [2, 0]], find matrix X.
Answer: A
X = [[5-3, 1-4], [2-(-1), 0-2]] = [[2, -3], [3, -2]].
3. The total cost of 2 notebooks and 3 pens is RM13, while 4 notebooks and 1 pen cost RM11. Which matrix equation models this scenario?
Answer: A
Let x = price of notebook, y = price of pen. 2x + 3y = 13 and 4x + y = 11. Matrix: [[2, 3], [4, 1]] [[x], [y]] = [[13], [11]].
4. Given matrix A = [4 -2 5]. What type of matrix is A?
Answer: B
Matrix A consists of a single row, so it is a row matrix (order 1 × 3).
5. Evaluate [2 5] [[3], [-1]].
Answer: C
[2(3) + 5(-1)] = [6 - 5] = [1].
6. Matrix M has order 2 × 3 and matrix N has order 3 × 4. What is the order of the product matrix MN?
Answer: A
For (2 × 3) × (3 × 4), inner dimensions match (3=3). The resulting matrix order is outer dimensions 2 × 4.
7. What is the order of a matrix with 3 rows and 2 columns?
Answer: A
The order of a matrix is written as rows × columns. 3 rows and 2 columns give order 3 × 2.
8. Calculate the determinant of matrix A = [[4, 2], [3, 2]].
Answer: B
det(A) = ad - bc = (4)(2) - (2)(3) = 8 - 6 = 2.
9. Given A B = I, where I is an identity matrix. Which statement is TRUE?
Answer: A
By definition, if A B = I, then B = A⁻¹ (B is the inverse matrix of A).
10. Calculate the result of [3 -1] + [4 6].
Answer: B
[3+4 -1+6] = [7 5].