To use the elimination method, you can add the two equations in a system of equations to eliminate one of the variables. Add the two equations.
{−9x+y=1010x−y=−9

What is the resulting equation?
Answers :

A 0+2y=10 plus 2 y is equal to 1

B x+0=1x plus 0 is equal to 1

C x+0=19x plus 0 is equal to 19

D 19x+2y=19

the correct answer is b. negative exponential growth.

step-by-step explanation:

you can tell it's an exponential function because it decreases rapidly then levels out and never touches the x-axis.

it is negative because the y-axis decreases as the x-axis increases.

therefore it is a negative exponential growth graph.

hope i !

step-by-step explanation:

; fx

you need to give us more information since we can't answer

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places