5х-15х+24 <-7
-10х<-7-24
-10х<-31 | (-1)
10х> 31
х> 3,1
S7 = ?
b2=b1*q=1/2
b3=b1*q^2=1/4
q = 1/2
b1=1
S7 = b1*(q^7 - 1)/q-1
S7 = -127/128 /-1/2
S7 = 127/64
4*3/8-9*7/9=6-7= -1. Ответ: -1.
)2x^2-9x=0
x(2x-9)=0
x=0
2x-9=0
x=9/2=4.5
<span>2)3x-x^2=0
x(3-x)=0
x=0
x=3</span>