Answer:
0dh 8/6
Step-by-step explanation:
You need to use all of them until you find the answer so lets fo this!
a. (-10,-12) x=-10 y=-12
3x+2y=6
3*(-10)+2*(-12)=6
-30-24=6
-54=6
This is incorrect,now we try the othe options
b.(10,12) x=10 y=12
3x+2y=6
3*10+2*12=6
30+24=6
54=6
This is incorrect then we try the other option
c. (-10,12) x=-10 y=12
3x+2y=6
3*(-10)+2*12=6
-30+24=6
6=6
And this is the correct answer. So the answer is c. (-10,12)
Answer
x=63
y=18
explanation
x+y=81
2x=7y
solve for x
x=(7/2)y
sub into first equation
(7/2)y+y=81
(9/2)y=81
y=18
sub into x equation
x=(7/2)(18)
x=63
Step-by-step explanation:The answer is 2
Answer:
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.