Question 1 if you don’t mind. I’m not sure what to x first

x= 2

y= -3

Step-by-step explanation:

Create a third equation by bringing the x over to right hand side to have y on its own to make solving easier.

4x-y = 11

-y =-4x+11

(divide by -1)

y= 4x-11 (equation 3)

Sub 3 into 1

5x + 2(4x-11) =4

5x + 8x-22 =4

13x=4+22

13x= 26

x= 26/13

x=2

y=4x-11

y= 4(2)-11

y= 8-11

y= -3

the circle graph is not a function.

step-by-step explanation:

the graph of the circle is not a function.

because for a graph to be a function, each value of x must give one value of y

in the circle, the values of x for -2< x< 2 each give 2 values of y.

hence this is not a function.

e^-kt = n/n0 = 0.79  

-kt = ln 0.79  

t = - ln 0.79/0.0001  

= 2357 years

step-by-step explanation: