Answer:
x=4 Postive
Step-by-step explanation:
See the steps below:)
First set up your two equations:
x + y = 90
x = 2y - 30
Then substitute what x equals in the second equation into the first equation:
(2y -30) + y = 90
Now solve for y:
3y -30 = 90
3y = 120
y = 40
Then use y = 40 and substitute the value for y into one of your original equations and solve for x. I'll choose the first one, but either one will work.
x+ 40 = 90
x = 50
So your solution is x = 50 and y = 40
We can then write an equation representing this problem as:
e−1.5mi=5.25mi
Now, add 1.5mi to each side of the equation to solve for e while keeping the equation balanced:
e−1.5mi+1.5mi=5.25mi+1.5mi
e−0=6.75mi
e=6.75mi
The plane's starting elevation was 6.75 miles
Hope this helps!
First, you want to establish your equations.
L=7W-2
P=60
This is what we already know. To find the width, we have to plug in what we know into P=2(L+W), our equation to find perimeter.
60=2(7W-2+W)
Now that we only have 1 variable, we can solve.
First, distribute the 2.
60=14W-4+2W
Next, combine like terms.
60=16W-4
Then, add four to both sides.
64=16W
Lastly, divide both sides by 16
W=4
To find the length, we plug in our width.
7W-2
7(4)-2
28-2
L=26
I think it is y=-.25
7*3 - 4y = 20
21 - 4y = 20
subtract 21 from each side
- 4y = - 1
divide each side by - 4
y= -.25
