9514 1404 393
Answer:
(x, y) = (7, -1)
Step-by-step explanation:
The expression for x makes it easy to use that for substitution.
3(-7y) +y = 20
-20y = 20 . . . . . collect terms
y = -1 . . . . . . . . . divide by -20
-7(-1) = x = 7 . . . use y in the second equation to find x
The solution is (x, y) = (7, -1).
If you are saying that the hypotenuse is 10 cm the you have to solve the following equation using the Pythagorean theory.
4^2 + b^2 = 10^2
16 + b^2 = 100
16 - 16 + b^2 = 100 - 16
b^2 = 84
Find 
RS => y - 5 = (8 - 5)/(1 - (-1)) (x - (-1))
y - 5 = 3/2 (x + 1) => slope = 3/2
ST => y - 8 = (-2 - 8)/(7 - 1) (x - 1)
y - 8 = -10/6 (x - 1) = -5/3 (x - 1) => slope = -5/3
TU => y - (-2) = (0 - (-2))/(2 - 7) (x - 7)
y + 2 = 2/5(x - 7) => slope = 2/5
UR => y = 5/(-1 - 2) (x - 2)
y = -5/3 (x - 2) => slope = -5/3
The median is the line joining the midpoints of the non-parallel sides.
Midpoint of RS = ((-1 + 1)/2, (5 + 8)/2) = (0, 13/2)
Midpoint of TU = ((7 + 2)/2, -2/2) = (9/2, -1)
Equation of the line joining (0, 13/2) and (9/2, -1) is given by y - 13/2 = (-1 - 13/2)/(9/2) x
y - 13/2 = (-15/2)/(9/2) x
y - 13/2 = -15/9x
18y - 117 = -30x
30x + 18y = 117
1 gallon= 8.345 pounds
11.81 gallons= ? Ibs
11.81*8.345= 98.5 Ibs (99)