A matrix is diagonal if

In other words, you want non-zero elements only when the indices of the row and the column are the same: the first element of the first row must be non zero, the second element of the second row must be non-zero, and so on. All other elements must be zero.
You would circle the 3 in 31, the 9 in 94, and the 1 in 17
4, there are 4 equal angles
Step-by-step explanation:
2.9 hours = 174mins
174 mins = 4.9miles
1 miles = 1740/49 mins
8.73 miles = 310.0mins (1dp)
Topic: Rate & Proportions
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