Use the method of elimination to solve the following simultaneous equations. -5p+q/2=-3/2 2p+3q/2=4 What are the following steps?
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To eliminate p, multiply the first equation by two, the second by 5 and add the results.
-5p+q/2=-3/2......(1) 2p+3q/2=4......(2) (1)x2 (-5p)x2+(q/2)x2=(-3/2)x2 -10p+q=-3 (2)x5 (2p)x5+(3q/2)x5=(4)x5 10p+15q/2=20 (-10p+q)+(10p+15q/2)=-3+20 16q/2=17 ↓↓↓ ??
Last edited by william24; Aug 20th 2012 at 02:36 AM.
$\displaystyle \left( -10p+q \right) + \left( 10p+\frac{15q}{2} \right)= \left( -10p+\frac{2q}{2} \right) + \left( 10p+\frac{15q}{2} \right) = \frac{17q}{2}$ Then $\displaystyle \frac{17q}{2} = 17 \implies q=2$
Thx for ur help. My answer booklet's answer is q=-2 and p=1 After I follow ur method to do, I also got the q=2 answer. Is there are somethin' wrong??
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