SOLUTION: please help me to solve this problem: Given the points P(-1,-2) Q(4,2) and R(1,m) in the coordinate plane. find the value of m so that PR + PQ is minimum. thanks!!!

Algebra.Com
Question 118344: please help me to solve this problem: Given the points P(-1,-2) Q(4,2) and R(1,m) in the coordinate plane. find the value of m so that PR + PQ is minimum.
thanks!!!

Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
Given the points P(-1,-2) Q(4,2) and R(1,m) in the coordinate plane. find the value of m so that PR + PQ is minimum.
---------------
PR = sqrt[(m+2)^2+(1+1)^2] = sqrt[m^2+2m+5]
PQ = sqrt[(2+2)^2+(4+1)^2] = sqrt[41]
--------------
PR + PQ = sqrt[m^2+2m+5] + sqrt[41]
--------------
To minimize the sum we need to minimize m^2+2m+5:
That occurs when m = -b/2a = -2/2 = -1
--------------
Cheers,
Stan H.

RELATED QUESTIONS

pls help me... Given the points P(-1,-2) Q(4,2) and R(1,m) in the coordinate plane. Find (answered by solver91311)
1. please help me with this question. M and F are complementary events. Also q and v are (answered by ikleyn)
P varies jointly as m and u, and varies inversely as q. Given that p=4, m=3 and u=2 when... (answered by Cromlix)
Given that Q= (3P-1)/2P+1, (a) Find the value of Q when P=2, ( I solved and Q=1) (b)... (answered by Theo)
Please help me find the value of r, so that the line that passes through each pair of... (answered by rfer)
Please help me solve this i have no idea what to do: determine the unknown coordinate so... (answered by Alan3354)
Please help me solve 1. (~m>p) * (~n>q) 2. ~(m*n) (answered by Edwin McCravy)
The general equation os a quadratic polynomial is p(x)=ax(squared)+bx+c with a,b,c all... (answered by longjonsilver)
Determine the value of (p+q+r); if p,q, and r are positive integers, p^q = 8, and r^(1/p) (answered by jim_thompson5910)