Question

a-6см b-? p-24см s -?

Answer 1

1) p = 2 * ( a + b ) ; p = 2a + 2b ; 2b = p - 2a ; b = 0,5 * ( p - 2a ) ; b = 0,5p - a 
b = 0,5 * 24 - 6 = 12 - 6 = 6 ( cм ) 
2) s = ab
s = 6 • 6 = 36 ( см2 )