# simultaneous Equation, i have the answers but cannot seem to get to them

• Nov 27th 2012, 08:22 AM
moleman87
simultaneous Equation, i have the answers but cannot seem to get to them
Hi all,

I have the following equations;

0 = A - (B/(50^2))
-8 = A - (B/(75^2))

B = -36000
A = -14.4

I think i may be failing somewhere with my rearranging of the formulas to subtract one from the other.

Any ideas?
• Nov 27th 2012, 09:14 AM
Plato
Re: simultaneous Equation, i have the answers but cannot seem to get to them
Quote:

Originally Posted by moleman87
Hi all,
I have the following equations;
0 = A - (B/(50^2))
-8 = A - (B/(75^2))

Rewrite them as:
$\displaystyle 50^2A - B=0$
$\displaystyle 75^2A -B= -8\cdot 75^2$
• Nov 27th 2012, 01:03 PM
HallsofIvy
Re: simultaneous Equation, i have the answers but cannot seem to get to them
Quote:

Originally Posted by moleman87
Hi all,

I have the following equations;

0 = A - (B/(50^2))
-8 = A - (B/(75^2))

What do you get if you subtract the second equation from the first?
0- (-8)= 8, of course, and A- A= 0. So what is -B/50^2- (-B/75^2)? (50= 25(2) and 75= 25(3). So 50^2= 25^2(4) while 75^2= 25^2(9). The common denominator is 25^2(4)(9).