Question

Ajutati-ma va rog .
3(x-2) la a 2 a + (x-5)(x+5)-2x(x-6)

Answer 1

3(x-2)² + (x-5)(x+5)-2x(x-6) = 3*(x²-4x+4)+x²-25-2x²+12x=
= 3x²-12x+12+x²-25-2x²+12x= 2x²-13.

Answer 2

3(x-2) la a 2 a + (x-5)(x+5)-2x(x-6)    folosim formula (a-b)²
3(x²-4x+4) + (x-5)(x+5)-2x(x-6)         folosim formula (a+b)(a-b)
3(x²-4x+4) + (x²-25)-2x²+12x
3x²-12x+12 + x²-25-2x²+12x     12x se reduce cu -12x
2x²-13=0
2x²=13
x²=13/2