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zimovet [89]
3 years ago
5

Use addition or substitution to find the value of y for this set of equations. 4x + 13y = 40 4x + 3y = -40

Mathematics
1 answer:
Aliun [14]3 years ago
5 0
4x + 13y = 40
4x + 3y = -40

multiply second equation by -1

4x + 13y = 40
-4x - 3y = 40

add equations together

10y = 80
y = 8

put y in either original equation

4x + 3(8) = -40
4x + 24 = -40

subtract 24 from both sides

4x = 64

x=16
y=8
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Now, we have to find z in the Ztable as such z has a pvalue of 1-\alpha.

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