What's the length of the |AC| ?

enter image source here

2 Answers
Sep 17, 2017

AC=5sqrt2AC=52

Explanation:

If AB ⊥ BCABBC, and AB=5AB=5, then BC=5BC=5. This is a right angled triangle, which means sidesa^2+b^2=c^2a2+b2=c2. In this case a=AB=5,a=AB=5, b=BC=5,b=BC=5, and c=ACc=AC. Therefor
5^2+5^2=(AC)^252+52=(AC)2
25+25=(AC)^225+25=(AC)2
50=(AC)^250=(AC)2
sqrt50=AC50=AC

From here we can simplify sqrt5050, since
sqrt50=sqrt(5*5*2)=5sqrt250=552=52

I hope I helped!

Sep 17, 2017

AC=8 1/3cm.AC=813cm.

Explanation:

As BH=3BH=3 and AB=5AB=5, as Delta ABH is right angled at H, using Pythagoras Theorem

AH=sqrt(5^2-3^2)=sqrt(25-9)=sqrt16=4

In a right angled triangle, right angled at /_B, if we connect midpoint of hypotenuse to B, then

BD=AD=DC.

Ler this be x and then HD=x-3 and using Pythagoras Theorem on DeltaAHD, we have

AH^2+HD^2=AD^2 or 4^2+(x-3)^2=x^2

i.e. x^2-6x+9+16=x^2

or 6x=25 and x=25/6=4 1/6

Hence, AC=25/6xx2=25/3=8 1/3cm.