Answer:
x=92 y=23
Step-by-step explanation:
Let them be x and y respectively
so given
x-y=69
and
x/y=4 x=4y
so we can write
x-y=69
as
4y-y=69 3y=69 y= 69/3 = 23
now y is 23
so putting in any equation will give the value of x
so
x-23=69 x=92
Answer:
B. D (-4, 3)
Step-by-step explanation:
In quadrant II x value is -ve and y value is positive.
Answer:
1
Step-by-step explanation:
Xy= 120
x= 7+y
(7+y)(y) = 120
y^2 + 7y - 120 = 0
(y + 15) (y - 8) = 0
Since we are finding two positive numbers,
If y= 8 then x= 15
The two numbers are 8 and 15
3x - y + z = 5 . . . (1)
x + 3y + 3z = -6 . . . (2)
x + 4y - 2z = 12 . . . (3)
From (2), x = -6 - 3y - 3z . . . (4)
Substituting for x in (1) and (3) gives
3(-6 - 3y - 3z) - y + z = 5 => -18 - 9y - 9z - y + z = 5 => -10y - 8z = 23 . . (5)
-6 - 3y - 3z + 4y - 2z = 12 => y - 5z = 18 . . . (6)
(6) x 10 => 10y - 50z = 180 . . . (7)
(5) + (7) => -58z = 203
z = 203/-58 = -3.5
From (6), y - 5(-3.5) = 18 => y = 18 - 17.5 = 0.5
From (4), x = -6 - 3(0.5) - 3(-3.5) = -6 - 1.5 + 10.5 = 3
x = 3, y = 0.5, z = -3.5
