Question 890652
r, boat speed in absence of any current
c, speed of current



_______________speed________time________distance
upstream_______r-c__________5___________150
downstream_____r+c__________3___________150



SYSTEM OF EQUATIONS
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{{{highlight_green((r-c)*5=150)}}}
{{{highlight_green((r+c)*3=150)}}}
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Those are two simultaneous linear equations.