Question

1.2x +5

dla x=-3

2.3x2 +2x -1

dla x=10

3.5x2 - y

dla x=-1/4 y=1/5

Answer 1

1,2x+5 , x=-3

1,2*(-3)+5=-3,6+5=1,4

 

2,3x^2+2x-1 , x=10

2,3*10^2+2*10-1=2,3*100+2*10-1=230+20-1=250-1=249

 

3,5x^2-y . x=1/4, y =1/5

3,5*(1/4)^2-1/5=3,5*1/16-1/5=3,5*0,0625-0,2=0,21875-0,2=0,01875

Answer 2

1.

2x +5  = 2 * (-3) + 5 = - 6 + 5 = -1

 

 

2.

3x2 +2x -1 = 3 * 10^2 + 2 * 10 - 1 = 300 + 20 - 1 = 319

 

 

3.

5x2 - y = 5 * (-1/4)^2 - 1/5 = 5 * 1/16 - 1/5 = 5/16 - 1/5 = 25/80 - 16/80 = 9/80