Hello!
To solve this problem, we will use a system of equations. We will have one number be x and the other y. We will use substitutions to solve for each variable.
x+y=9
x=2y-9
To solve for the two numbers, we need to solve the top equation. The second equation shows that x=2y-9. In the first equation, we can replace 2y-9 for x and solve.
2y-9+y=9
3y-9=9
3y=18
y=6
We now know the value of y. Now we need to find x. We can plug in 6 for y in the second equation to find x.
x=2·6-9
x=12-9
x=3
Just to check, we will plug these two numbers into the first equation.
3+6=9
9=9
Our two numbers are three and six.
I hope this helps!
The equality used is Subtraction property of equality
Option A is correct
Step-by-step explanation:
We need to identify which option best explains or justifies Step 1.
Step 1 is: 
The given equation is: 
To get the equation for step 1 we need to subtract c on both sides of equation i.e using subtraction property of equality


So, The equality used is Subtraction property of equality
Option A is correct.
Keywords: Solving Quadratic Equations
Learn more about Solving Quadratic Equations at:
#learnwithBrainly
Answer:
Hi there, I believe the answer to this equation is: 2.8
Step-by-step explanation:
Subtract 7 on both sides so
5n+7=21-7
you are left with 5n=14 you need to get n by itself so divide 5 on both sides.
5n/5 = 14/5
n=2.8
Hope this is correct :)
Have a great day
Take 2000 divide 76 =26.3 so the elevator can carry 26 boxes