Question

b) 2y+5y(2-y)=3*5y^2

c)2(x-2)^2+5(7x-3)=2(x-1)(x+1)

^2 -potega

Answer 1

b)

 

 

c)

 

Answer 2

b) 2y+5y(2-y)=3*5y^2

2y+10y-5y² =15y² 

20y² -12y=0

y(20y-12)=0

 

y=0 lub 20y-12=0------>y=0 lub y=12/20--------> y=0 lub y=3/5

 

c)2(x-2)^2+5(7x-3)=2(x-1)(x+1)

2(x²+4-4x)+35x-15=2(x² -1)

2x²+8-8x+35x-15=2x² -2

27x-7=-2

27x=-2+7

27x=5

x=5/27