Geometry Practice Test 1

By Pythagoras theorem,
${\left(\mathit{x}\mathit{y}\right)}^2$ = ${\left(\mathit{x}\mathit{z}\right)}^2+{\left(\mathit{y}\mathit{z}\right)}^2$
${\left(17\right)}^2$ = ${\left(\mathit{a}+9\right)}^2+{\left(\mathit{a}+2\right)}^2$
289 = ${\mathit{a}}^2$ + 81+18a + ${\mathit{a}}^2$+ 4 + 4a

$2{\mathit{a}}^2$ + 22a + 85 = 289
$2{\mathit{a}}^2$ + 22a − 204 = 0
${\mathit{a}}^2$ +11a −102 = 0
(a +17)(a − b) = 0
a = 6 , a = −17→ not possible
Radius = 6 cm