The units digit of a two-digit number is twice the tens digit. if the digits are reversed, the new number is 9 less than the original number. what is the original number?

36

Step-by-step explanation:

Here is the correct and complete question: The units digit of a two-digit number is twice the tens digit. If the digits are reversed, the new number is 9 less than twice the original number. What is the original number?

Lets assume the original number be"10y+x". (x is unit digit and y is 10th digit)

∴ if number is reversed then resulting number be "10x+y".

As given: x= 2y

        and

Now, solving the equation to get original number.

Distributing 2 to 10y and x, then opening the parenthesis.

⇒

subtracting by (2x+y) on both side.

⇒

subtituting the value of "x", which is equal to 2y.

∴

⇒

subtracting both side by (16y-9)

⇒

cross multiplying

We get,

y=3

∵x= 2y

∴ x= 6

Therefore, the original number will be 36 as x is the unit number and y as tenth number.

(1, –1), (16, –4), (36, –6)

step-by-step explanation:

given that the function is

this can also be written as

we have to graph this function and check which list of points lie on the graph

see attachment for graph:

we find that the points lying are (1,-1) (16,-4) and (36,-6)

since square root is there we find that x can only be posiitve but y can be since square root both positive and negative.