1)5t^2-4t=0
t (5t-4)=0
t=0, 5t=4
t=4/5
2)(5x-2)(2x+1)=10x^2-3x+10
10x^2+5x-4x-2-10x^2+3x-10=0
4x-12=0
4x=12
x=3
<span>1) 506000 = 5,06</span>·10⁵<span>
2) 0,0123 = 1,12</span>·10⁻⁴
<span>
№2
</span>
<span>
№3
</span>
<span>
</span>
допустим, V- корень, тогда
V3*(3)^2/V5*15=V27/V75=V9/V25=3/5
Формулы, которые я использую
(a - b)(a + b) = a^2 - b^2
(a - b)^2 = a^2 - 2ab + b^2
а)
(x - 2y)(x + 2y) + 4y^2 = x^2 - 4y^2 + 4y^2 = x^2
б)
(5x - 1)^2 + 10x = 25x^2 - 10x + 1 + 10x = 25x^2 + 1
3y+x=12, y-4x+9=0, K(x,y)=?
---
x+3y=12
-4x+y=-9
----
x=12-3y
-4x+y=-9
-----
x=12-3y
-4(12-3y)+y=-9
---
x=12-3y
-48+12y+y=-9
----
x=12-3y
13y=48-9
---
x=12-3y
13y=39
---
x=12-3y
y=3
---
x=12-3.3
y=3
---
x=12-9
y=3
---
x=3
y=3
----
K(3,3)
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