Задача 13596 (4x+5)^2=(4x-7)^2...

vk381210900

09.02.2017

(4x+5)^2=(4x-7)^2

SOVA

09.02.2017

★

(4x+5)^2=(4x–7)^2;
(4x+5)^2-(4x–7)^2=0;
(4x+5-4x+7)*(4x+5+4x-7)=0
12*(8x-2)=0
8x-2=0
8x=2
x=1/4
О т в е т. 1/4

magos

2020-06-05 11:16:39

(4x+5)^2 = (4x-7)^2
16x^2+40x+25 = 16x^2-56x+49
40x+25 = -56x+49
40x+56x = 49-25
96x = 24
x = 24/96
x = 0,25