Answer:
2. x = -16 y = -10.5
3. x = 4
4. x = 3 y = 2/9 or 0.2222222222222...
Step-by-step explanation:
2.
in my stategy, you plus -5x + 8y = -4 with 6x - 8y = -12
+8y and -8y could delete each other, then y will be gone.
-5x + 6y = 1x = x because -5 + 6 = 1
so then you could got x = (-4) + (-12) which means x = -16
if x = -16 that will then means
(-5) x (-16) + 8y = -4
80 + 8y = -4
8y = -4 - 80
8y = -84
y = -10.5
3.
This question has already given you that y = -5
that means, 3x + 6 × (-5) = -18
3x + -30 = -18
3x = -18 - (-30)
3x = 12
x = 4
4.
Like the 2. qestion, you first plus the 2 equation together,
+9y + -9y = 0
-7x + 4x = -3x
-19 + 10 = -9
than means
-3x = -9
x = 3
then put the x = 3 in one of the equation.
4 x 3 - 9y = 10
12 - 9y = 10
-9y = 10 - 12
-9y = -2
-7 x 3 + 9y = -19
-21 + 9y = -19
9y = -19 + 21
9y = 2
y = 2/9 or 0.2222222222...
Wish this could help you!
