# Math Help - Simultaneous equation problem

1. ## Simultaneous equation problem

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?

2. ## Re: Simultaneous equation problem

To eliminate p, multiply the first equation by two, the second by 5 and add the results.

3. ## Re: Simultaneous equation problem

-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
??

4. ## Re: Simultaneous equation problem

$\left( -10p+q \right) + \left( 10p+\frac{15q}{2} \right)= \left( -10p+\frac{2q}{2} \right) + \left( 10p+\frac{15q}{2} \right) = \frac{17q}{2}$

Then

$\frac{17q}{2} = 17 \implies q=2$

5. ## Re: Simultaneous equation problem

Thx for ur help.