Answer:
[tex]Area= \frac{17 \sqrt{865} }{4} \: {units}^{2} [/tex]
Step-by-step explanation:
From Pythagoras theorem,
[tex] {h}^{2} = {12}^{2} + { (\frac{17}{2} )}^{2} [/tex]
[tex]{h}^{2} = \frac{865}{4} [/tex]
[tex]h = \frac{ \sqrt{865} }{2} [/tex]
The area of the isosceles triangle is
[tex]Area= \frac{1}{2} bh[/tex]
[tex]Area= \frac{1}{2} \times 17 \times \frac{ \sqrt{865} }{2} = \frac{17 \sqrt{865} }{4} [/tex]