I'd suggest re-wording your question:
"How do I find the ordered pair (x,y) that solves this system of linear equations?"
One way of doing that would be to substitute y=5x+7 into the other equation:
-3x - 2(5x+7) = -12. Solve this for x. Once you have a value for x, subst. that value into y=5x+7 to find the corresponding y value.
Then write the ordered pair (x,y). That's it.
Answer:
C
Step-by-step explanation:
It makes sense
Answer:
x = 3.53 ft
y - 3.53 ft
z = 3.53 ft
Step-by-step explanation:
given details
volume = 44 ft^3
let cardboard dimension is x and y and height be z
we know that area of given cardboard without lid is given as
A = xy + 2xy + 2yz
xyz = 44 ft^3
To minimize area we have
A = xy + 2x (44/xy) + 2y(44/xy)
A = xy + (44/y) + (44/x)
we have

................1


..............2
from 1 and 2

xy(y-x) = 0
xy = 0 or y = x
from geometry of probelem
x ≠ 0 and y ≠ 0
so y = x
x^3 = 44
x = 3.53 ft = y
z = 44/xy = 3.53