Question

Решите уравнение:
а) 16х^2-(4х-5)^2=15
б) х(х+3)-(х-1)^2=4
в)(2х+3)^2-(2х-3)^2=48
15б

Answer 1

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Answer 2

а) 16х^2-(4х-5)^2=15
16x^2-(16x^2-40x+25)=15
16x^2-16x^2+40x-25=15
40х-25=15
40х=40
х=1

б) х(х+3)-(х-1)^2=4
x^2+3x-(x^2-2x+1)=4
x^2+3x-x^2+2x-1=4
3x+2x-1=4
5x-1=4
5x=5
x=1

в) (2х+3)^2-(2х-3)^2=48 
4x^2+12x+9-(4x^2-12x+9)=48
12x+9+12x-9=48
24x=48
x=48:24
x=2