Answer:
(3, - 1)
Step-by-step explanation:
5x - 4y = -11
2x + 3y = -9
Multiply the top equation by 2 and the bottom equation by - 5 to cancel out the x's.
10x - 8y = - 22
- 10x - 15y = 45
Cancel out x's.
-8y = - 22
- 15y = 45
Add like terms.
- 23y = 23
Can't have a negative variable to flip them.
-23 = 23y
Divide.
y = - 1
Input y into one of the equations and solve for x.
2x + 3(-1) = -9
Simplify.
2x -3 = -9
Cancel out -3 by adding 3.
2x = -6
Divide.
x - -3
Answer:
sister = 6 years
John=18 years
Step-by-step explanation:
A(S) + 12 = 3 * A(S), subtracting A(S) from both sides one gets 12 = 2 * A(S). Now dividing both sides by 2 we get A(S) = 12/2 = 6 . Therefore, the age of the sister is 6 years when her brother John is three times as old, that is 18 years.
Answer:6
Step-by-step explanation:Reorder
2
2
and
−
x
-
x
.
y
=
−
x
+
2
y
=
-
x
+
2
3
x
+
3
y
=
6
3
x
+
3
y
=
6
Replace all occurrences of
y
y
in
3
x
+
3
y
=
6
3
x
+
3
y
=
6
with
−
x
+
2
-
x
+
2
.
y
=
−
x
+
2
y
=
-
x
+
2
3
x
+
3
(
−
x
+
2
)
=
6
3
x
+
3
(
-
x
+
2
)
=
6
Simplify
3
x
+
3
(
−
x
+
2
)
3
x
+
3
(
-
x
+
2
)
.
Tap for more steps...
y
=
−
x
+
2
y
=
-
x
+
2
6
=
6
6
=
6
Since
6
=
6
6
=
6
, the equation will always be true.
y
=
−
x
+
2
y
=
-
x
+
2
Always true
Remove any equations from the system that are always true.
y
=
−
x
+
2
Answer:
(−∞, ∞) and (−∞, ∞)
Step-by-step explanation:
One example (of many) might be y = 2x. The domain and range of this function are (−∞, ∞) and (−∞, ∞).
