When solving system equations, we can use substitution method or elimination. Today I'm using substitution method.
First name the 2 equations.
3x + y = 3 (1)
x + y = 2 (2)
Now pick one equation and express one algebra in forms of the other.
From (2),
x = 2 - y (3)
Now substitute (3) into (1),
3(2-y) + y = 3
6 - 3y + y = 3
6 - 2y = 3
6 - 3 = 2y
y = 1.5
Now substitute y = 1.5 into (2)
x + 1. 5 = 2
x = 2 - 1.5
x = 0.5
Therefore the answer is x = 0.5 and y = 1.5
$220.87 , (it would be $220.88 if you have to round up though
Answer:
69
Step-by-step explanation:
5(
–
q+6)=
–
20
5q–30=
–
20
Add -5 to both sides
Subtract -5 from both sides
Multiply both sides by -5
Divide both sides by -5
Apply the distributive property
5q=
Add 30 to both sides
q=
Divide both sides by 5 would be 69
The correct answer is A. 10
8 divided by 0.8 = 10
10x0.8=8
Answer:
Prove set equality by showing that for any element
,
if and only if
.
Example:
.
.
.
.
.
Step-by-step explanation:
Proof for
for any element
:
Assume that
. Thus,
and
.
Since
, either
or
(or both.)
- If
, then combined with
,
. - Similarly, if
, then combined with
,
.
Thus, either
or
(or both.)
Therefore,
as required.
Proof for
:
Assume that
. Thus, either
or
(or both.)
- If
, then
and
. Notice that
since the contrapositive of that statement,
, is true. Therefore,
and thus
. - Otherwise, if
, then
and
. Similarly,
implies
. Therefore,
.
Either way,
.
Therefore,
implies
, as required.