Step-by-step explanation:
a.
simply add both equations
x + y = 2
-3x - y = 5
----------------
-2x + 0 = 7
x = -7/2
x + y = 2
-7/2 + y = 2
y = 2 + 7/2 = 4/2 + 7/2 = 11/2
b.
1/2 x + 2y = -13
x - 4y = 8
first multiply the first equating by 2
x + 4y = -26
x - 4y = 8
--------------------
2x + 0 = -18
x = -18/2 = -9
x - 4y = 8
-9 - 4y = 8
-4y = 17
y = -17/4
Answer:
discriminant is zero (0)
Step-by-step explanation:
Actually, you have a double root here: {6, 6}: "two real, equal roots." That tells us immediately that the value of the discriminant was zero (0).
Okay, all we need to do is divide 8 from both sides:
-104/8=-13
So x=-13
:D
Answer:
104
Step-by-step explanation:
Any expression multiplied by 0 equals 0
when adding or subtracting 0, the quantity doesn't change
