Question

Suppose ABCD is a rectangle. Find AB and AD if point M is the midpoint of

Answer 1

We know that
Perimeter=2AB+2AD=34 in-----> AB+AD=17-----> AB=17-AD-----> equation 1

MA=MD
MA²=AB²+(AD/2)²
for the triangle AMD
AD²=[MA²+MD²]----> AD²=2*[MA²]----> AD²=2*[AB²+(AD/2)²]---> equation 2

I substitute 1 in 2

AD²=2*[(17-AD)²+(AD/2)²]----> AD²=2*[289-34AD+AD²+0.25AD²]

AD²=578-68AD+2.50AD²--------> 1.50AD²-68AD+578

1.50AD²-68AD+578=0

 using a graph tool to solve the quadratic equation

see the attached figure

AD1=11.33 in

AD2=34 in----------is not solution because (AB+AD=17)

Solution is AD=11.33 in

AB=17-11.33--------> 17-11.33-----> AB=5.67 in

 the answer is

AD=11.33 in

AB=5.67 in