(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Use Cramer's rule to solve for y (only). Call the 3x3 determinant D:

(a) ax+by = 1

cx+dy=0

(b) ax+by+cz=1

dx+ey+fz=0

gx+hy+iz=0

2. Relevant equations

Cramer's Rule: x=A^{-1}*b

3. The attempt at a solution

(a) So far I have,

y= [det [a 1; c 0] / det [a b; c d]} = (0-c)/(ad-bc)=-c/(ad-bc)

I don't know how to proceed...

Same with part (b),

y= [det[a 1 c; d 0 f; g o i]/det[a b c; d e f; g h i]] = (fg-di)/(aei+bfg+cdh-ceg-afh-ibd)

Is there a way to simplify this?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Cramer's Rule to solve for y

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