Question

Zapisz w jak najprostszej postaci:
a)2xy-8x+6xy-2x+10y=
b) (3a+5b-9)-(3a-5b+6)=
c)3(2x-5)-2(3x+4)=
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dla x=2
3(x ²-2x+3)-2(x ²-5x-1)=

Answer 1

A)2xy-8x+6xy-2x+10y= 8xy-10x+10y
b) (3a+5b-9)-(3a-5b+6)= 3a+5b-9-3a+5b-6=10b-15
c)3(2x-5)-2(3x+4)=6x-15-6x+8=-7
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dla x=2
3(x ²-2x+3)-2(x ²-5x-1)= 3(2²×2+3)-2(2²-5×2-1)=3(4×2+3)-2(4-10-1)=3×11-2×(-7)=33-(-14)= 33+14=47


pozdrawiam ;)

Answer 2

A) 8xy-10x+10y
b)3a+5b+9+3a+5b-6= 6a+10b+3
c)6x-15-6x-8= -23

3(2²-2*2+3)-2 (2²-5*2-1)= 3(4-4+3)-2(4-10-1)=12-12+9-8+20+2=23

Answer 3

A)2xy-8x+6xy-2x+10y=
8xy-10x+10y

b) (3a+5b-9)-(3a-5b+6)=
3a+5b-9-3a+5b-6=
10b-6

c)3(2x-5)-2(3x+4)= zmienisz znak na przeciwny bo masz minus przed nawiasem !!!
6x-15-6x-8=
-23
-----
dla x=2
3(x ²-2x+3)-2(x ²-5x-1)= 3x²-6x+9-2x²+10x+2= x²+4x+11
x²+4x+11=2²+4*2+11=4+8+11=23