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.
Answer:
sorry i need points :(
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Step-by-step explanation:
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Answer: $0.35 which is the same as 35 cents
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Work Shown:
3 cookies = $1.05
3/3 cookies = $1.05/3
1 cookie = $0.35 = 35 cents
Answer:
24
Step-by-step explanation:
IDK
Answer: z = -5/-3
Step-by-step explanation:
(3z−11)+(6−6z)
3z - 11 + 6 - 6z
- 6z + 3z - 11 + 6
- 3z - 5
z = -5/-3