Odpowiedź:
a) 4x-2(x+4)-5=4x-2x-8-3=2x-11
b) 6(3x-4)-3(3x+5)=6+12x-24-3-9x-15=3x-36
c) 40x+20/5-1/3 (15x+21)=5(8x+4)/5 - 1/3 *3(5x-7)= 5(8x+4)/5 - 1/3 (5x-7)=8x+4-(5x+7)= 8x+4-5x-7=3x-3
d) 3x*(-2y)+x*(-5)2️⃣x-4x2️⃣y(-3y)-7x(-4)y(-1/2)x
=3x2️⃣*(-2y)+x*(-5) y2️⃣x-4x2️⃣y*(-3y)-7x*(-4)y*(-1/2)x =3x2️⃣*(-2y)+x2️⃣*(-5)y2️⃣-4x2️⃣y*(-3y)-7x*(-4)y*(-1/2)
x=3x2️⃣*(-2y)+x2️⃣*(-5)y2️⃣ -4x2️⃣y*(-3y)-7x2️⃣*(-4)y* (-1/2)= x2️⃣*(3x(-2y) - 5y2️⃣-4y*(-3y)-7*4y*1/2)=x2️⃣*(-3*2y-5y2️⃣-4y*(-3y)-7*4y*1/2) =x2️⃣*(-3*2y-5y2️⃣+4y+3y-7*4y*1/2)=x2️⃣*(-3*2y-5y2️⃣+4y*3y-7*2y)=x2️⃣*(-6y-5y2️⃣+4y*3y-7*2y)=x2️⃣*(-6y-5y2️⃣+12y2️⃣-7*2y)= x2️⃣*(-6y-5y2️⃣+12y-14y)= x2️⃣*(-20y-5y2️⃣+12y2️⃣) =x2️⃣*(-20y+7y2️⃣) =x2️⃣*(-y*(20-7y))=-x2️⃣y*(20-7y)
Szczegółowe wyjaśnienie:
*= mnożenie
2️⃣= potęga
