0
r2 + r - 20 = 0(r + 5)(r - 4) = 0r + 5 = 0 or r - 4 = 0r = -5 or r = 4
r9 - 6 = 12
then r is 2
x = (r + st)/r is the expression that represents x in the equation rx - st = r.
Since r varies directly with s, we have
r = ks (replace k with 5 and s with 7)
r = (5)(7)
r = 35
To solve for r, you can multiply both sides of the equation by 7 to isolate r. This gives you r = 1400 * 7, which simplifies to r = 9800.