Four positive integers satisfy the following equations:
pq+2p+q = 348
qr+4q+3r = 208
rs+8r+6s = 722
What are p, q, r, and s?
p q + 2 p + q = 348,
q r + 4 q + 3 r = 208,
r s + 8 r + 6 s = 722, solve for p, q, r, s
r = 16 and s = 27 and p = 34 and q = 8
I/m using a technique that I "borrowed" from a really good mathematician on here, Alan !!!!
pq + 2p + q = 348
qr + 4q + 3r = 208
rs + 8r + 6s = 722
Manipulating the first equation
p (q + 2) = (348 - 1q)
p = (348 - 1q) / (q + 2)
p = [ (350 - 1( q + 2) ] / (q + 2)
p = (350) / ( q + 2) - 1
Manipulating the second equation
qr + 4q + 3r = 208
q ( r + 4) = 208 - 3r
q = ( 208 - 3r) ( r + 4)
q = [ (220 -3(r + 4) ] / (r + 4)
q = (220) / (r + 4) - 3
Manipulating the third equation
rs + 8r + 6s = 722
r (s + 8) = 722 - 6s
r = (722 - 6s) / ( s + 8)
r = [722 - 6(s + 8)] / (s + 8)
r = [ 770 - 6(s +8) ] / (s + 8)
r = [ 770 ] / (s + 8) - 6
Note that 770 factors as 2 * 5 * 7 * 11 = 2 * (35) * 11 = 2 * (27 + 8) * 11
If we let s = 27 then we have that
r = 770 / 35 - 6 = 22 - 6 = 16
q= (220) / (16 + 4) - 3 = 11 - 3 = 8
p = (350) / ( 8 + 2) - 1 = 35 - 1 = 34