Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

You are not logged in.

## #1 2005-09-05 11:05:48

the_white_sheep
Member
Registered: 2005-09-05
Posts: 9

Hi

I know this may look easy for some people but I'm just grasping it. Please look at the following simultaneous equation and see what you get. Thanks alot.

3p + 2q = 9
4p - 6q  = 25

Please let me know how you worked it out as well.

Thanks

Hozan

Offline

## #2 2005-09-05 11:35:11

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

Compare 3p and 4p.   Okay.  Then compare 2q and -6q.  Oh, 2 times 3 is 6, so that will be the easy way to solve.
We will get rid of the q and find p.   Multiply 3p +2q = 9 by 3 and add it to the other equation.
So 9p + 6q = 27.   Add it to second equation.  13p + zero q = 52
p = 4.  Put 4 back into any equation and get q.  q = -3/2

Another way is to graph the two lines on graph paper and see where they intersect.

igloo myrtilles fourmis

Offline