Question

taking X =5/6,y=-7/3,z=2/9


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Answer 1

Step-by-step explanation:

For example, if we add the first two equations, we get:

x + y + y + z = 13

We already know that x + z = 9, so we can substitute to yield:

2y + 9 = 13

2y = 4

y = 2

Now that we know the value of y, we can return to:

x + y = 6

By substitution we have:

x + 2 = 6

x = 4

By the same process we can solve either of the equations for z by substituting the value of either x or y.

y + z = 7

2 + z = 7

z = 5

Now that we know that x = 4, y = 2, and z = 5, we can sum their values and divide by 3 to get their average.

4 + 2 + 5 = 11

11 divides by 3 is 11/3, or approximately 3.67.