Question

Zad 21,strona 67. Zbiór zadań

b)(x+5)²-(x-3)²=x+1

c)(x+1)²+(x-3)(x+3)-2=2(x-1)²

d)(2-x)(2+x)+(x+3)²=x-7

f)(x-5)²-(x-3)²=4(x-2 )

Bardzo proszę o rozwiązanie!!!!!!!!!!

Answer 1

b)

(x+5)²-(x-3)²=x+1

x²+10x+25-(x²-6x+9)=x+1

x²+10x+25-x²+6x-9=x+1

16x-x=1-16

15x=-15/:15

x=-1

 

c)

(x+1)²+(x-3)(x+3)-2=2(x-1)²

x²+2x+1+x²-9-2=2(x²-2x+1)

2x²+2x-10=2x²-4x+2

2x²-2x²+2x+4x=2+10

6x=12/:6

x=2

d)

(2-x)(2+x)+(x+3)²=x-7

4-x²+x²+6x+9=x-7

6x-x=-7-13

5x=-20/:5

x=-4

f)

(x-5)²-(x-3)²=4(x-2 )

x²-10x+25-(x²-6x+9)=4x-8

x²-10x+25-x²+6x-9=4x-8

-4x-4x=-8-16

-8x=-24/:(-8)

x=3