Answer: The determinant of the coefficient matrix is -15 and x = 3, y = 4, z = 1.
Step-by-step explanation: The given system of linear equations is :

We are given to find the determinant of the coefficient matrix and to find the values of x, y and z.
The determinant of the co-efficient matrix is given by

Now, from equations (ii) and (iii), we have

Substituting the value of y and z from equations (iv) and (v) in equation (i), we get

From equations (iv) and (v), we get

Thus, the determinant of the coefficient matrix is -15 and x = 3, y = 4, z = 1.
Answer:
6 dm
Step-by-step explanation:
Triangle DBE is similar to triangle ABC, so their side lengths are proportional.
DE/AC = DB/AB
The length of DB can be found from ...
DB +AD = AB
DB = AB -AD = (15 -10) dm = 5 dm
So, we can fill in the proportion:
DE/(18 dm) = (5 dm)/(15 dm)
DE = (18 dm)·(1/3) . . . . . . . . . . simplify, multiply by 18 dm
DE = 6 dm
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It can be helpful to draw and label a figure.
Answer:
f
Step-by-step explanation:
The variables would always be the letter