The last one as we can see that as the wight increases, the miles per gallon decreases.
X would be -31/4 and (-65 plus or minus i root 3)/8
Answer:
(x, y) = (6, -7)
Step-by-step explanation:
Assuming you want to solve the equations for x and y, you can divide the second equation by 2 to get
x -2y = 20
then add 2y to obtain an expression for x:
x = 20 +2y
Substituting this into the first equation gives ...
5(20 +2y) +3y = 9
100 +13y = 9 . . . . . . eliminate parentheses, collect terms
13y = -91 . . . . . . . . . .subtract 100
y = -7 . . . . . . . . . . . . .divide by 13
Using this in our expression for x, we find ...
x = 20 +2(-7) = 6
The solution is (x, y) = (6, -7).
Step-by-step explanation:
![y = 3x + 5 \\ 2x + 4y = 6 \\ subsitution \\ 2x + 4(3x + 5) = 6 \\ 2x + 12x + 20 = 6 \\ 14x = - 14 \\ x = - 1 \\ y = 3x + 5 \\ y = - 3 + 5 \\ y = 2](https://tex.z-dn.net/?f=y%20%3D%203x%20%2B%205%20%5C%5C%202x%20%2B%204y%20%3D%206%20%5C%5C%20subsitution%20%5C%5C%202x%20%2B%204%283x%20%2B%205%29%20%3D%206%20%5C%5C%202x%20%2B%2012x%20%2B%2020%20%3D%206%20%5C%5C%2014x%20%3D%20%20-%2014%20%5C%5C%20x%20%3D%20%20-%201%20%5C%5C%20y%20%3D%203x%20%2B%205%20%5C%5C%20y%20%3D%20%20-%203%20%2B%205%20%5C%5C%20y%20%3D%202)