1)[tex]S= \frac{I*h}{2} => S=10*6/2=30
S=(C1*C2)/2 => C1*C2=2*S[/tex]
C1*C2=2*30=60
2)-2x<-12 => 2x>12 => x>6
3)3a=5b => b=(3/5)a => 3a-b=3a-(3/5)*a=(6/3)a=2a
3a=5b => a=(5/3)b => 2a-b=(10/3)b-b=7/3b
[tex] \frac{3a-b}{2a-b} = [tex] \frac{2a}{ \frac{7b}{3} } = \frac{a}{b} * \frac{3*2}{7} = \frac{3}{5} * \frac{6}7}= \frac{18}{35} [/tex]
4)a-b=-21 => a=b-21
5a=2b => 5(b-21)=2b => 5b-105=2b => 3b=105 => b=35 => a=35-21=14
a*b=14*35=490
5)a+b=156 => a=156-b
[tex] \frac{a+24}{b-32} =1 => a+24=b-32[/tex]
156-b+24=b-32 =>2b=156+24+32 => 2b=212 => b=106
a=156-106=50