Y=3x-8
x=-4
y=3•(-4)-8
y=-20
Решение
log₅x=(log₃125)·log₅3+log₂0,5<span>
log₅x = (log₃5</span>³<span>) * log₅3 + log₂ 2</span>⁻¹
log₅x = 3*(log₃5 * log₅3) - log₂ 2
<span>log₅x = 3 - 1
</span><span>log₅ x = 2
</span>x = 5²
x = 25
3/(x-5)+8/x=2 x≠5, x≠0
3x+8(x-5)=2x(x-5)
3x+8x-40=2x²-10x
2x²-21x+40=0
D=21²-4*40*2= 121=+-11²
x1=(21-11)/4=10/4=2 1/2
x²=(21+11)/4=33/4=8 1/4
2/(-√(2n)+6))=2 (-√(2n)-6) / (-√(2n) +6)( -√(2n)-6)= -2(√(2n)+6)/(2n-36)=
=(√(2n)+6)/(18-n)
6*50=300
4*10=40
300+40=340 копеек или 3 рубля 40 копеек