Calculate the height of an equilateral triangle each of whose sides measures 12 cm.
ABC is an equilateral triangle with side 12cm
AE⊥BC
In ABD and
ACD
∠ADB=∠ADC=90
AB=AC=12cm
AD=AD (COMMON)
ABD
ACD
AD2+BD2=AB2
AD2+62=122
AD2+36=144
AD2=144-36
AD2=108
AD=
AD=10.39 cm